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A Programming Method for Mean Behavior of Fourier Coefficients of Modular Forms on Sparse Sequences
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作者 HU Yuanrui YAO Weili 《数学进展》 北大核心 2025年第4期709-724,共16页
Let f be a primitive holomorphic cusp form with even integral weight k≥2 for the full modular groupΓ=SL(2,Z)andλ_(sym^(j)f)(n)be the n-th coefficient of Dirichlet series of j-th symmetric L-function L(s,sym^(j)f)at... Let f be a primitive holomorphic cusp form with even integral weight k≥2 for the full modular groupΓ=SL(2,Z)andλ_(sym^(j)f)(n)be the n-th coefficient of Dirichlet series of j-th symmetric L-function L(s,sym^(j)f)attached to f.In this paper,we study the mean value distribution over a specific sparse sequence of positive integers of the following sum∑(a^(2)+b^(2)+c^(2)+d^(2)≤x(a,b,c,d)∈Z^(4))λ_(sym^(j))^(i)f(a^(2)+b^(2)+c^(2)+d^(2))where j≥2 is a given positive integer,i=2,3,4 andαis sufficiently large.We utilize Python programming to design algorithms for higher power conditions,combining Perron's formula,latest results of representations of natural integers as sums of squares,as well as analytic properties and subconvexity and convexity bounds of automorphic L-functions,to ensure the accuracy and verifiability of asymptotic formulas.The conclusion we obtained improves previous results and extends them to a more general settings. 展开更多
关键词 automorphic L-function holomorphic cusp form Fourier coefficient
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AI-Enabled Computer Programming Course Teaching Reform
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作者 Yao Dai 《Journal of Electronic Research and Application》 2025年第3期90-96,共7页
With the rapid development of modern science and technology,the era of artificial intelligence has quietly come.Against the background of the new era,students’learning needs,learning resource acquisition methods,teac... With the rapid development of modern science and technology,the era of artificial intelligence has quietly come.Against the background of the new era,students’learning needs,learning resource acquisition methods,teachers’teaching concepts,teaching tools,and so on have changed significantly.How to carry out teaching reform based on this change has become one of the important issues facing educators,and the same is true for the teaching of computer programming courses.This paper focuses on the teaching reform of AI-enabled computer programming courses,analyzes its basic problems,and puts forward corresponding reform countermeasures to provide a useful reference for front-line teachers. 展开更多
关键词 AI Computer programming
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Research on Teaching Reform Strategies of Python Programming Course Based on Artificial Intelligence Technology
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作者 Hong Chen 《Journal of Electronic Research and Application》 2025年第5期25-29,共5页
As one of the core courses for computer-related majors,the Python programming course has become increasingly important in the era of artificial intelligence.It aims to help students develop good computer thinking and ... As one of the core courses for computer-related majors,the Python programming course has become increasingly important in the era of artificial intelligence.It aims to help students develop good computer thinking and improve their abilities in programming and data analysis.The application of artificial intelligence technology in the teaching of Python programming courses is of great significance for optimizing the allocation of teaching resources,enriching students’learning experience,and significantly improving teaching quality.Based on this,this paper first briefly expounds on the importance of applying artificial intelligence technology in the teaching of Python programming courses.On this basis,it focuses on exploring effective strategies for the teaching reform of Python programming courses based on artificial intelligence technology,hoping to provide new ideas for the teaching of Python programming courses and contribute to cultivating more Python programming talents with artificial intelligence literacy. 展开更多
关键词 Artificial intelligence technology Python programming course Teaching reform Effective strategies
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Teaching Reform of the C Programming Language Course Integrating OBE Concept and AI Assistance under the New Engineering Background
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作者 Arzigul Ahat Gulnaz Alimjan 《Journal of Contemporary Educational Research》 2025年第7期197-202,共6页
With the continuous advancement of the New Engineering Education initiative,universities are raising the standards for cultivating engineering talents.C Programming Language,as a core course for computer science and r... With the continuous advancement of the New Engineering Education initiative,universities are raising the standards for cultivating engineering talents.C Programming Language,as a core course for computer science and related majors,plays a fundamental role in developing logical thinking,programming skills,and engineering practice.However,problems such as outdated content,weak practical connections,and single assessment methods still exist in current teaching,which affects both learning outcomes and students’skill development.Based on the outcome-based education(OBE)approach and supported by AI-assisted teaching tools,this paper proposes a reform plan focusing on teaching content,instructional methods,and evaluation systems.The goal is to enhance students’overall abilities and practical innovation skills,and to align the course more closely with modern industry needs. 展开更多
关键词 New Engineering C programming Language Teaching reform OBE concept AI-assisted instruction
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Application Effect of SECI Program in Improving Clinical Nurses’Information Teaching Ability
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作者 Xue Li Jiao Mi +1 位作者 Mengxue Chen Yue Hu 《Journal of Clinical and Nursing Research》 2025年第10期80-85,共6页
Objective:To investigate the application effect of the SECI theoretical model-based training program in enhancing clinical nursing teachers‘information-based teaching capabilities.Methods:A self-control study design ... Objective:To investigate the application effect of the SECI theoretical model-based training program in enhancing clinical nursing teachers‘information-based teaching capabilities.Methods:A self-control study design was adopted,with 124 clinical nursing teachers from a tertiary hospital participating in the SECI training program from January 2024 to June 2025.The program was implemented through four stages:“Establishing Teacher Community(Socialization)”,“Case Teaching(Extravagant)”,“Integration of Discipline and Research(Fusion)”,and“Routine Application of Teaching(Implicit)”.Self-designed questionnaires were used to assess teachers’information-based teaching capabilities before and after training,covering four dimensions:awareness and attitude towards information-based teaching,foundational skills,teaching practice,and professional practice.Data analysis was performed using SPSS 26.0.Results:Post-training,the total score of clinical nursing teachers’information-based teaching capabilities increased from(53.47±15.56)to(78.92±12.34),showing statistically significant differences(t=15.732,P<0.001).Scores in all dimensions also showed significant improvements(P<0.05).Multivariate linear regression analysis revealed that educational background(β=0.198,P=0.026)and professional title(β=0.184,P=0.040)were primary influencing factors for pre-training information-based teaching capabilities,while their impact weakened post-training.Conclusion:The training program based on SECI theory effectively enhances clinical nursing educators’digital teaching capabilities.Its structured,spiral-up knowledge transformation process helps bridge competency gaps among teachers from diverse backgrounds,facilitates the mutual conversion and deep integration of tacit and explicit knowledge,and provides a practical new model for developing digital teaching competencies in clinical nursing education. 展开更多
关键词 Clinical nursing teachers Effect evaluation Information-based teaching ability SECI model Training program
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Value Iteration-Based Distributed Adaptive Dynamic Programming for Multi-Player Differential Game With Incomplete Information
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作者 Yun Zhang Yuqi Wang Yunze Cai 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期436-447,共12页
In this paper,a distributed adaptive dynamic programming(ADP)framework based on value iteration is proposed for multi-player differential games.In the game setting,players have no access to the information of others&#... In this paper,a distributed adaptive dynamic programming(ADP)framework based on value iteration is proposed for multi-player differential games.In the game setting,players have no access to the information of others'system parameters or control laws.Each player adopts an on-policy value iteration algorithm as the basic learning framework.To deal with the incomplete information structure,players collect a period of system trajectory data to compensate for the lack of information.The policy updating step is implemented by a nonlinear optimization problem aiming to search for the proximal admissible policy.Theoretical analysis shows that by adopting proximal policy searching rules,the approximated policies can converge to a neighborhood of equilibrium policies.The efficacy of our method is illustrated by three examples,which also demonstrate that the proposed method can accelerate the learning process compared with the centralized learning framework. 展开更多
关键词 Distributed adaptive dynamic programming incomplete information multi-player differential game(MPDG) value iteration
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The"4+4"Medical Doctor(MD)Pilot Program at PUMC:Implementation,Performance,and Prospects 被引量:3
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作者 Jing-Jing Yi Wei-Wei Xu +6 位作者 Chao Ma He Di Jing Jin Le Zeng Wen-Ji Tu Wen-Wen Sun Qin Zhang 《Chinese Medical Sciences Journal》 CAS CSCD 2024年第2期144-148,共5页
Peking Union Medical College(PUMC)launched the"4+4"Medical Doctor(MD)pilot program in 2018,admitting students with non-medical backgrounds from top universities,aligning with national medical talent training... Peking Union Medical College(PUMC)launched the"4+4"Medical Doctor(MD)pilot program in 2018,admitting students with non-medical backgrounds from top universities,aligning with national medical talent training policies to foster diverse and eager learners in medicine.On the occasion of the graduation of the first class of the"4+4"MD pilot class at PUMC in 2023,we reviewed the teaching reform in the pilot program and carried out a systematic survey and interviews with students,faculties,and management staff of the pilot class.This article reports on the measures taken by the pilot class at PUMC in enrollment and curriculum setting,and demonstrates the achievements of the pilot class in terms of student academic background structure,knowledge acquisition and skill learning,scientific research ability,and course evaluation.The results indicated that the pilot class had met the national demand for the"Medicine+X"talent training model.More specifically,with a diverse academic backgrounds,the pilot class graduates had academic levels comparable to the eight-year medical education graduates,and their scientific research abilities were satisfactory.The pilot program at PUMC will optimize the curriculum setting,strengthen the construction of faculty,learning resources,and teaching facilities,and reform the academic evaluation methods,thus deepening the reform of medical education and improving the"4+4"MD program as a novel medical education model. 展开更多
关键词 "4+4"MD pilot program teaching reform medical education
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融合卷积CR-FFD与偏置Transformer胶囊网络的单视图三维物体重建
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作者 连远锋 赵泽欣 《计算机辅助设计与图形学学报》 北大核心 2025年第4期623-634,共12页
针对复杂拓扑结构物体单视图三维重建过程中二维图像与三维形状之间难以准确映射的问题,提出一种融合卷积Catmull-Rom样条自由形变(CR-FFD)与偏置Transformer胶囊网络的单视图三维重建方法.首先通过Catmull-Rom样条基函数对点云模型控... 针对复杂拓扑结构物体单视图三维重建过程中二维图像与三维形状之间难以准确映射的问题,提出一种融合卷积Catmull-Rom样条自由形变(CR-FFD)与偏置Transformer胶囊网络的单视图三维重建方法.首先通过Catmull-Rom样条基函数对点云模型控制点进行插值,保持点云模型形变局部拓扑结构的一致性;然后提出卷积神经网络最小二乘求逆解法,通过非线性参数映射加速求解过程;最后设计偏置注意力Transformer胶囊网络增强局部特征表达能力,捕获点云形状的细粒度特征.实验结果表明,在ShapeNet数据集上,所提方法的EMD指标平均值为3.84, CD指标平均值为3.71;在Pix3D数据集上, EMD指标平均值为5.51, CD指标平均值为5.39;与已有的单视图点云三维重建方法相比,该方法有效地提升单视图的三维重建结果,能够从不同角度保持重建的一致性. 展开更多
关键词 CATMULL-ROM样条 自由形变 三维重建 胶囊网络 偏置注意力
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基于Autoform正弦波形膜盘工艺优化与回弹补偿
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作者 毕凤阳 姜旭 +2 位作者 宁慧燕 王晓宏 宋泊霖 《世界有色金属》 2025年第14期213-216,共4页
针对金属正弦波形膜盘尺寸较大,成形过程中回弹大的问题,基于Autoform建立了膜盘冲压成形有限元模型,并以压边力、摩擦系数和模具间隙为优化工艺参数,回弹量为优化目标,通过正交试验法设计优化试验,根据极差分析结果表明,摩擦系数对回... 针对金属正弦波形膜盘尺寸较大,成形过程中回弹大的问题,基于Autoform建立了膜盘冲压成形有限元模型,并以压边力、摩擦系数和模具间隙为优化工艺参数,回弹量为优化目标,通过正交试验法设计优化试验,根据极差分析结果表明,摩擦系数对回弹量的影响最大,最优工艺参数组合为压边力800KN、摩擦系数0.11、模具间隙1.05mm。为了进一步改善回弹问题,采用四次预先补偿对模具型面进行修正,最终将膜盘正弦波曲面偏差控制在约0.1mm以内。通过成形试验与形状偏差测试,验证了所设计的冲压模具的精度,尺寸偏差能够控制在0.0~0.15mm之间。 展开更多
关键词 冲压成形 工艺优化 正弦波形膜盘 有限元 正交试验 回弹补偿
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Corrosion and Copper Foil Formation Behavior of Laser-Welded Joint and Spin-Formed Materials of Commercially Pure Titanium in H_(2)SO_(4)/CuSO_(4) Electrolyte 被引量:1
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作者 Ren Lina Song Yanfei +4 位作者 Qi Liang Yang Jian Yang Jiadian Lei Xiaowei Zhang Jianxun 《稀有金属材料与工程》 北大核心 2025年第6期1467-1477,共11页
Based on the microstructure characterization,electrochemical impedance spectroscopy,potentiodynamic polarization,and immersion corrosion,this work comparatively analyzed the differences in the electrochemical corrosio... Based on the microstructure characterization,electrochemical impedance spectroscopy,potentiodynamic polarization,and immersion corrosion,this work comparatively analyzed the differences in the electrochemical corrosion morphology and post-foil formation surface morphology of laser beam welded(LBW)sample and spin-formed sample,and compared the corrosion resistance and Cu foil formation ability of two samples in H_(2)SO_(4)/NaCl solution and CuSO_(4) reducing electrolyte.Results show that in H_(2)SO_(4) and NaCl solutions,LBW sample and spin-formed sample exhibit excellent passivation ability and corrosion resistance.Both samples show uniform corrosion morphologies and similar corrosion resistance in the strong acidic solution containing Cl^(-).Meanwhile,the Cu foil formation ability of the welded joint is similar to that of the spin-formed sample,and both samples obtain intact Cu foils with high-quality surfaces and small differences in properties. 展开更多
关键词 Ti cathode laser beam welding spin forming CORROSION Cu foil electroplating
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Intelligent prediction model of tunnelling-induced building deformation based on genetic programming and its application
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作者 XU Jing-min WANG Chen-cheng +3 位作者 CHENG Zhi-liang XU Tao ZHANG Ding-wen LI Zi-li 《Journal of Central South University》 CSCD 2024年第11期3885-3899,共15页
This paper aims to explore the ability of genetic programming(GP)to achieve the intelligent prediction of tunnelling-induced building deformation considering the multifactor impact.A total of 1099 groups of data obtai... This paper aims to explore the ability of genetic programming(GP)to achieve the intelligent prediction of tunnelling-induced building deformation considering the multifactor impact.A total of 1099 groups of data obtained from 22 geotechnical centrifuge tests are used for model development and analysis using GP.Tunnel volume loss,building eccentricity,soil density,building transverse width,building shear stiffness and building load are selected as the inputs,and shear distortion is selected as the output.Results suggest that the proposed intelligent prediction model is capable of providing a reasonable and accurate prediction of framed building shear distortion due to tunnel construction with realistic conditions,highlighting the important roles of shear stiffness of framed buildings and the pressure beneath the foundation on structural deformation.It has been proven that the proposed model is efficient and feasible to analyze relevant engineering problems by parametric analysis and comparative analysis.The findings demonstrate the great potential of GP approaches in predicting building distortion caused by tunnelling.The proposed equation can be used for the quick and intelligent prediction of tunnelling induced building deformation,providing valuable guidance for the practical design and risk assessment of urban tunnel construction projects. 展开更多
关键词 building deformation genetic programming tunnel construction modification factor
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Interleukin-17A facilitates tumor progression via upregulating programmed death ligand-1 expression in hepatocellular carcinoma 被引量:1
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作者 Zhong-Xia Yang Li-Ting Zhang +2 位作者 Xiao-Jun Liu Xue-Bin Peng Xiao-Rong Mao 《World Journal of Gastrointestinal Oncology》 SCIE 2025年第1期176-198,共23页
BACKGROUND Hepatocellular carcinoma(HCC)is an inflammation-associated tumor with a dismal prognosis.Immunotherapy has become an important treatment strategy for HCC,as immunity is closely related to inflammation in th... BACKGROUND Hepatocellular carcinoma(HCC)is an inflammation-associated tumor with a dismal prognosis.Immunotherapy has become an important treatment strategy for HCC,as immunity is closely related to inflammation in the tumor microenvir-onment.Inflammation regulates the expression of programmed death ligand-1(PD-L1)in the immunosuppressive tumor microenvironment and affects im-munotherapy efficacy.Interleukin-17A(IL-17A)is involved in the remodeling of the tumor microenvironment and plays a protumor or antitumor role in different tumors.We hypothesized that IL-17A participates in tumor progression by affe-cting the level of immune checkpoint molecules in HCC.The upregulation of PD-L1 expression in HCC cells by IL-17A was assessed by reverse transcription PCR,western blotting,and flow cytometry.Mechanistic studies were conducted with gene knockout models and pathway inhibitors.The function of IL-17A in immune evasion was explored through coculture of T cells and HCC cells.The effects of IL-17A on the malignant biological behaviors of HCC cells were evaluated in vitro,and the antitumor effects of an IL-17A inhibitor and its synergistic effects with a PD-L1 inhibitor were studied in vivo.RESULTS IL-17A upregulated PD-L1 expression in HCC cells in a dose-dependent manner,whereas IL-17A receptor knockout or treatment with a small mothers against decapentaplegic 2 inhibitor diminished the PD-L1 expression induced by IL-17A.IL-17A enhanced the survival of HCC cells in the coculture system.IL-17A increased the viability,G2/M ratio,and migration of HCC cells and decreased the apoptotic index.Cyclin D1,VEGF,MMP9,and Bcl-1 expression increased after IL-17A treatment,whereas BAX expression decreased.The combination of IL-17A and PD-L1 inhibitors showed synergistic antitumor efficacy and increased cluster of differentiation 8+T lymphocyte infiltration in an HCC mouse model.CONCLUSION IL-17A upregulates PD-L1 expression via the IL-17A receptor/phosphorylation-small mothers against decapenta-plegic 2 signaling pathway in HCC cells.Blocking IL-17A enhances the therapeutic efficacy of PD-L1 antibodies in HCC in vivo. 展开更多
关键词 INTERLEUKIN-17A programmed death ligand-1 Interleukin-17A receptor Small mothers against decapentaplegic 2 Hepatocellular carcinoma IMMUNOTHERAPY
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Relationship between Helicobacter pylori infection and programmed death-ligand 1 in gastric cancer:A meta-analysis 被引量:1
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作者 Hong-Chang Yang Cheng-Feng Fu +3 位作者 Li-Jun Qiao Gen-He Long Li-Fen Yang Biao Yao 《World Journal of Clinical Oncology》 2025年第4期280-290,共11页
BACKGROUND Gastric cancer(GC)is one of the most common malignancies worldwide,and Helicobacter pylori(HP)infection is a well-established risk factor for its development.Programmed death-ligand 1(PD-L1)expression is a ... BACKGROUND Gastric cancer(GC)is one of the most common malignancies worldwide,and Helicobacter pylori(HP)infection is a well-established risk factor for its development.Programmed death-ligand 1(PD-L1)expression is a crucial biomarker for predicting the efficacy of immune checkpoint inhibitors in cancer treatment.While HP infection and PD-L1 expression in GC may be linked,the relationship between them remains unclear,in part because there have been conflicting results reported from various studies.AIM To perform a meta-analysis to assess the relationship between HP and PD-L1 expression in patients with GC.METHODS A systematic literature review was conducted using PubMed,Embase,Cochrane Library,and Web of Science databases.Observational studies that examined the association between HP infection and PD-L1 expression in patients with GC were included.Odds ratios and 95%confidence intervals were calculated to estimate the association.Heterogeneity was assessed using Cochrane’s Q test and I²statistic.A random-effects model was used due to significant heterogeneity across studies.RESULTS Fourteen studies involving a total of 3069 patients with GC were included.The pooled analysis showed a significant association between HP infection and increased PD-L1 expression in GC tissues(odd ratio=1.69,95%confidence interval:1.24-2.29,P<0.001,I^(2)=59%).Sensitivity analyses confirmed the robustness of these findings.Subgroup analyses did not show significant variation based on geographic region,sample size,or method of PD-L1 assessment.Publication bias was minimal,as shown by funnel plots and Egger’s regression test.CONCLUSION HP infection is associated with increased PD-L1 expression in GC,suggesting that HP status may influence the response to programmed cell death protein 1/PD-L1 blockade therapy. 展开更多
关键词 Helicobacter pylori Gastric cancer programmed cell death protein 1/programmed death-ligand 1 Immune checkpoint blockade therapy PATHOGENESIS
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Glia-to-neuron reprogramming to the rescue?
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作者 Jack W.Hickmott Cindi M.Morshead 《Neural Regeneration Research》 SCIE CAS 2025年第5期1395-1396,共2页
Over the last two decades,the dogma that cell fate is immutable has been increasingly challenged,with important implications for regenerative medicine.The brea kth rough discovery that induced pluripotent stem cells c... Over the last two decades,the dogma that cell fate is immutable has been increasingly challenged,with important implications for regenerative medicine.The brea kth rough discovery that induced pluripotent stem cells could be generated from adult mouse fibroblasts is powerful proof that cell fate can be changed.An exciting extension of the discovery of cell fate impermanence is the direct cellular reprogram ming hypothesis-that terminally differentiated cells can be reprogrammed into other adult cell fates without first passing through a stem cell state. 展开更多
关键词 programming PASSING proof
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Neurocircuit regeneration by extracellular matrix reprogramming
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作者 Shengzhang Su Ian N.Levasseur Kimberly M.Alonge 《Neural Regeneration Research》 SCIE CAS 2025年第8期2300-2301,共2页
The brain's extracellular matrix(ECM),which is comprised of protein and glycosaminoglycan(GAG)scaffolds,constitutes 20%-40% of the human brain and is considered one of the largest influencers on brain cell functio... The brain's extracellular matrix(ECM),which is comprised of protein and glycosaminoglycan(GAG)scaffolds,constitutes 20%-40% of the human brain and is considered one of the largest influencers on brain cell functioning(Soles et al.,2023).Synthesized by neural and glial cells,the brain's ECM regulates a myriad of homeostatic cellular processes,including neuronal plasticity and firing(Miyata et al.,2012),cation buffering(Moraws ki et al.,2015),and glia-neuron interactions(Anderson et al.,2016).Considering the diversity of functions,dynamic remodeling of the brain's ECM indicates that this understudied medium is an active participant in both normal physiology and neurological diseases. 展开更多
关键词 MATRIX programMING
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Cytoplasmic and nuclear programmed death ligand 1 expression in peritumoral stromal cells in breast cancer:Prognostic and predictive value 被引量:1
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作者 Evgeniya Yu Zubareva Marina A Senchukova Natalia V Saidler 《World Journal of Experimental Medicine》 2025年第2期150-170,共21页
BACKGROUND Breast cancer(BC)continues to occupy a leading position in terms of morbidity and mortality from malignant neoplasms among the female population.One of the promising markers associated with BC progression i... BACKGROUND Breast cancer(BC)continues to occupy a leading position in terms of morbidity and mortality from malignant neoplasms among the female population.One of the promising markers associated with BC progression is programmed death ligand 1(PD-L1).Previously,we investigated PD-L1 expression in BC via a new antibody against programmed cell death protein 1 ligand 1(PDCD1 LG1)and reported that high PDCD1 LG1 expression in tumor cells is an independent factor for a high risk of regional metastasis in patients with BC.However,the prognostic significance of PDCD1 LG1 expression in BC stromal cells has not been adequately studied.AIM To study the features of PDCD1 LG1 expression in BC stromal cells and its relationship with BC clinicopathological characteristics.METHODS In a prospective single-center observational study,tumor samples from 148 patients with newly diagnosed BC were examined.The tumor sections were immunohistochemically stained with antibodies against PDCD1 LG1.In the tumor samples,the PDCD1 LG1-positive lymphocyte(PDCD1 LG1+LF)score,presence of nuclear PDCD1 LG1 expression in the LFs,PDCD1 LG1 expression in polymorphic cell infiltrates(PDCD1 LG1+polymorphic cell infiltrates[PCIs]),and cells of the fibroblastic stroma and endothelial cells of the tumor microvessels were assessed.Statistical analyses were performed using Statistica 10.0 software.RESULTS A PDCD1 LG1+LF score≥3 was detected more often at stages N0 and N3 than at N1 and N2(P=0.03).Moderate and pronounced PDCD1 LG1+PCIs and the presence of PDCD1 LG1+fibroblastic stroma were associated with negative estrogen receptor status(P=0.0008 and P=0.03,respectively),human epidermal growth factor receptor 2-positive(HER2+)BC(P<0.00001 and P=0.0005),and luminal B HER2+,non-luminal HER2+and triple-negative BC(P<0.00001 and P=0.004).The risk of metastasis to regional lymph nodes(RLNs)depend on lymphovascular invasion(LVI)and the PDCD1 LG1+LF score.In the absence of LVI and a PDCD1 LG1+LF score<3 or≥3,metastases in RLNs were absent in 66.6%and 93.9%of patients with BC,respectively.In the presence of LVI and a PDCD1 LG1+LF score<3 or≥3,metastases in RLNs were detected in 82.6%and 92.7%of patients with BC,respectively.CONCLUSION The results indicated that the combined assessment of the PDCD1 LG1+LF score and LVI can improve the accuracy of predicting the risk of metastasis to RLNs in patients with BC. 展开更多
关键词 Breast cancer programmed death-ligand 1 Regional metastasis Tumor stroma
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Distribution,species richness,and relative importance of different plant life forms across drylands in China 被引量:1
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作者 Shuran Yao Weigang Hu +16 位作者 Mingfei Ji Abraham Allan Degen Qiajun Du Muhammad Adnan Akram Yuan Sun Ying Sun Yan Deng Longwei Dong Haiyang Gong Qingqing Hou Shubin Xie Xiaoting Wang Jinzhi Ran Bernhard Schmid Qinfeng Guo Karl J.Niklas Jianming Deng 《Plant Diversity》 2025年第2期273-281,共9页
Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmen... Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmental gradients.Particularly,the relative importance(RIV)of different plant life forms in a community and how they vary with environmental variables are still unclear.To fill these gaps,we determined plant diversity of ephemeral plants,annual herbs,perennial herbs,and woody plants from 187 sites across drylands in China.The SR patterns of herbaceous plants,especially perennial herbs,and their RIV in plant communities increased with increasing precipitation and soil nutrient content;however,the RIV of annual herbs was not altered along these gradients.The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality.The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments.An obvious shift emerged in plant community composition,SR and their critical impact factors at 238.5 mm of mean annual precipitation(MAP).In mesic regions(>238.5 mm),herbs were the dominant species,and the SR displayed a relatively slow decreasing rate with increasing aridity,which was mediated mainly by MAP and soil nutrients.In arid regions(<238.5 mm),woody plants were the dominant species,and the SR displayed a relatively fast decreasing rate with increasing aridity,which was mediated mainly by climate variables,especially precipitation.Our findings highlight the importance of comparative life form studies in community structure and biodiversity,as their responses to gradients differed substantially on a large scale. 展开更多
关键词 DRYLANDS Environmental gradients Plant life forms Relative importance Species richness THRESHOLD
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Geometric size and forming force prediction in incremental flanging:A new analytical model 被引量:1
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作者 Chong TIAN Dawei ZHANG +1 位作者 Guangcan YANG Shengdun ZHAO 《Chinese Journal of Aeronautics》 2025年第2期519-540,共22页
A new analytical model for geometric size and forming force prediction in incremental flanging(IF)is presented in this work.The complex deformation characteristics of IF are considered in the modeling process,which ca... A new analytical model for geometric size and forming force prediction in incremental flanging(IF)is presented in this work.The complex deformation characteristics of IF are considered in the modeling process,which can accurately describe the strain and stress states in IF.Based on strain analysis,the model can predict the material thickness distribution and neck height after IF.By considering contact area,strain characteristics,material thickness changes,and friction,the model can predict specific moments and corresponding values of maximum axial forming force and maximum horizontal forming force during IF.In addition,an IF experiment involving different tool diameters,flanging diameters,and opening hole diameters is conducted.On the basis of the experimental strain paths,the strain characteristics of different deformation zones are studied,and the stable strain ratio is quantitatively described through two dimensionless parameters:relative tool diameter and relative hole diameter.Then,the changing of material thickness and forming force in IF,and the variation of minimum material thickness,neck height,maximum axial forming force,and maximum horizontal forming force with flanging parameters are studied,and the reliability of the analytical model is verified in this process.Finally,the influence of the horizontal forming force on the tool design and the fluctuation of the forming force are explained. 展开更多
关键词 Incremental flanging Analytical model Strain characteristic Geometric size forming force
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A new multi-DOF envelope forming process for fabricating spiral bevel gears with back taper tooth 被引量:1
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作者 Xinghui HAN Yanhui WANG +3 位作者 Lin HUA Wuhao ZHUANG Fangyan ZHENG Wei FENG 《Chinese Journal of Aeronautics》 2025年第1期568-585,共18页
Spiral bevel gears are critical transmission components,and are widely used in the aerospace field.This paper proposes a new multi-DOF envelope forming process for fabricating spiral bevel gears.Firstly,the multi-DOF ... Spiral bevel gears are critical transmission components,and are widely used in the aerospace field.This paper proposes a new multi-DOF envelope forming process for fabricating spiral bevel gears.Firstly,the multi-DOF envelope forming principle of spiral bevel gears is proposed.Secondly,the design methods for the envelope tool geometry and movement are proposed based on the envelope geometry and movement relationships.Thirdly,the metal flow and tooth filling laws are revealed through 3D FE simulation of the multi-DOF envelope forming process of a typical spiral bevel gear.Fourthly,a new method for separating the envelope tool and the formed spiral bevel gear with back taper tooth is proposed to avoid their interference.Finally,experiments on multi-DOF envelope forming of this typical spiral bevel gear are conducted using new heavy load multi-DOF envelope forming equipment.The simulation and experimental results show the feasibility of the proposed multi-DOF envelope forming process for fabricating spiral bevel gears with back taper tooth and the corresponding process design methods. 展开更多
关键词 Multi-DOF envelope forming Spiral bevel gear Back taper tooth Metal flow Process design
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Safe flight corridor constrained sequential convex programming for efficient trajectory generation of fixed-wing UAVs 被引量:2
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作者 Jing SUN Guangtong XU +2 位作者 Zhu WANG Teng LONG Jingliang SUN 《Chinese Journal of Aeronautics》 2025年第1期537-550,共14页
Generating dynamically feasible trajectory for fixed-wing Unmanned Aerial Vehicles(UAVs)in dense obstacle environments remains computationally intractable.This paper proposes a Safe Flight Corridor constrained Sequent... Generating dynamically feasible trajectory for fixed-wing Unmanned Aerial Vehicles(UAVs)in dense obstacle environments remains computationally intractable.This paper proposes a Safe Flight Corridor constrained Sequential Convex Programming(SFC-SCP)to improve the computation efficiency and reliability of trajectory generation.SFC-SCP combines the front-end convex polyhedron SFC construction and back-end SCP-based trajectory optimization.A Sparse A^(*)Search(SAS)driven SFC construction method is designed to efficiently generate polyhedron SFC according to the geometric relation among obstacles and collision-free waypoints.Via transforming the nonconvex obstacle-avoidance constraints to linear inequality constraints,SFC can mitigate infeasibility of trajectory planning and reduce computation complexity.Then,SCP casts the nonlinear trajectory optimization subject to SFC into convex programming subproblems to decrease the problem complexity.In addition,a convex optimizer based on interior point method is customized,where the search direction is calculated via successive elimination to further improve efficiency.Simulation experiments on dense obstacle scenarios show that SFC-SCP can generate dynamically feasible safe trajectory rapidly.Comparative studies with state-of-the-art SCP-based methods demonstrate the efficiency and reliability merits of SFC-SCP.Besides,the customized convex optimizer outperforms off-the-shelf optimizers in terms of computation time. 展开更多
关键词 Fixed-wing unmanned aerial vehicle Efficient trajectory planning Safe flight corridor Sequential convex programming Customized convex optimizer
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