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Diophantine equations and Fermat's last theorem for multivariate(skew-)polynomials

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Applied Mathematics(A Journal of chinese Universities) 2024年第1期39卷 159-173页

作者： PAN Jie JIA Yu-ming li {2. school of Mathematical sciences Zhejiang UniversityHangzhou 310058China Henan Experimental High school Zhengzhou 450003China

Fermat’s Last Theorem is a famous theorem in number theory which is diﬃcult to ***,it is known that the version of polynomials with one variable of Fermat’s Last Theorem over C can be proved very *** aim of this paper is to study the similar problems about Fermat’s Last Theorem for multivariate(skew)-polynomials with any characteristic.

关键词： Fermat's last theorem polynomial ring skew polynomial ring

Research on Jiuquan-Jiayuguan-Yumen Region's Dynamic Changing of Urbanization Based on Self-Organizing Model

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chinese Journal of Population,Resources and Environment 2005年第3期3卷 22-28页

作者： li ming 1,2.& fang chuanglin 2.1 graduate school of the chinese academy of sciences, Beijing 100039,{2. 2.Institute of Geographical sciences and Natural Resources Research, CAS, Beijing 100101, {2. graduate school of the{2. academy of sciences Beijing 100039 China Institute of Geographical sciences and Natural Resources Research CAS Beijing 100101 China

Based on the self-organizing modeling principle in the dissipative structure theory, the paper regards the migration coupling between the regions as the influence factor to create the model of regional urbanization simulation and prediction, which is more practical to simulate the space-time and dynamic evolvement characteristics of regional urbanization level. According to the historical data about the population and urbanization of Jiuquan, Jiayuguan andYumen cities, the past 50 years' dynamic evolvement trend is simulated and the following 50 years' dynamic evolvement trend is predicted with the urbanization dynamic evolvement model based on the self-organizing model. The analysis of effective factors such as economic increase, resources exploitation, ecosystem construction, traffic location, national policies, population migration are given, then the reasons of the dynamic evolvement differences of the three cities' urbanization are drawn. The study suggests that the self-organizing model is fit for the simulation of Jiuquan-Jiayuguan-Yumen regional urbanization level in the past 50 years, and the departure between the stimulant and the actual data is under 5%, so it can be used to predict the urbanization future of the three cities. The predicted results show that the regional population will reach 1.074 million and the regional urbanization level will be 72.56%.

关键词： self-organizing urbanization dynamic evolvement Jiuquan-Jiayuguan-Yumen region

Oscillation properties of eigenfunctions for Sturm-liouville problems with interface conditions via Prufer transformation

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Applied Mathematics(A Journal of chinese Universities) 2024年第2期39卷 191-200页

作者： li Zhi-yu li Kun CAI Jin-{2. QIN Jian-fang ZHENG Zhao-wen school of Mathematical sciences Qufu Normal UniversityQufu 273165China College of Mathematics and Systems Science Guangdong Polytechnic Normal UniversityGuangzhou 510665China

A class of Sturm-liouville problems with discontinuity is studied in this *** oscillation properties of eigenfunctions for Sturm-liouville problems with interface conditions are *** main method used in this paper is based on Prufer transformation,which is different from the classical ***,we give two examples to verify our main results.

关键词： Sturm-liouville problem interface condition oscillatory solution

Cone-beam computed tomography noise reduction method based on U-Net with convolutional block attention module in proton therapy

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Nuclear Science and Techniques 2024年第7期35卷 89-100页

作者： Xing-Yue Ruan Xiu-fang li Meng-Ya Guo Mei Chen {2. Lv Rui li Zhi-ling Chen Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai201800China University of chinese academy of{2. Beijing100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China Department of Radiation Oncology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Shanghai Key Laboratory of Proton therapy Shanghai201801China

Cone-beam computed tomography(CBCT) is mostly used for position verification during the treatment process. However,severe image artifacts in CBCT hinder its direct use in dose calculation and adaptive radiation therapy re-planning for proton therapy. In this study, an improved U-Net neural network named CBAM-U-Net was proposed for CBCT noise reduction in proton therapy, which is a CBCT denoised U-Net network with convolutional block attention modules. The datasets contained 2. groups of head and neck images. The CT images were registered to CBCT images as ground truth. The original CBCT denoised U-Net network, sCTU-Net, was trained for model performance comparison. The synthetic CT(SCT) images generated by CBAM-U-Net and the original sCTU-Net are called CBAM-SCT and U-Net-SCT images, respectively. The HU accuracies of the CT, CBCT, and SCT images were compared using four metrics: mean absolute error(MAE), root mean square error(RMSE), peak signal-to-noise ratio(PSNR), and structure similarity index measure(SSIM). The mean values of the MAE, RMSE, PSNR, and SSIM of CBAM-SCT images were 2..80 HU, 64.63 HU, 52.2. dB, and 0.9919, respectively,which were superior to those of the U-Net-SCT images. To evaluate dosimetric accuracy, the range accuracy was compared for a single-energy proton beam. The γ-index pass rates of a 4 cm × 4 cm scanned field and simple plan were calculated to compare the effects of the noise reduction capabilities of the original U-Net and CBAM-U-Net on the dose calculation results. CBAM-U-Net reduced noise more effectively than sCTU-Net, particularly in high-density tissues. We proposed a CBAM-U-Net model for CBCT noise reduction in proton therapy. Owing to the excellent noise reduction capabilities of CBAM-U-Net, the proposed model provided relatively explicit information regarding patient tissues. Moreover, it maybe be used in dose calculation and adaptive treatment planning in the future.

关键词： Proton therapy Cone-beam CT CBAM-U-Net γ-index

Run-and-Tumble Dynamics and Mechanotaxis Discovered in Microglial Migration

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Research 2024年第2期2023卷 95-103页

作者： Yiyu Zhang Da Wei Xiaochen Wang Boyi Wang ming li Haiping {2. Yi Peng Qihui Fan {2.fu Ye Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China school of Physical sciences University of Chinese Academy of SciencesBeijing 100049China Wenzhou Institute University of Chinese Academy of SciencesWenzhouZhejang 325000China Songshan Lake Materials Laboratory DongguanGuangdong 523808China school of Science East China University of Science and TechnologyShanghai 200237China Oujang Laboratory(Zhejiang Lab for Regenerative Medicine Vision and Brain Health)WenzhouZhejiang 325000China

Microglia are resident macrophage cells in the central nervous system that search for pathogens or abnormal neural activities and migrate to resolve the *** effective search and targeted motion of macrophages mean dearly to maintaining a healthy brain,yet little is known about their migration *** this work,we study microglial motion with and without the presence of external *** discover that the cells are promptly attracted by the applied forces(i.e.,mechanotaxis),which is a tactic behavior as yet unconfirmed in ***,in both the explorative and the targeted migration,microglia display dynamics that is strikingly analogous to bacterial run-and-tumble motion.A closer examination reveals that microglial run-and-tumble is more sophisticated,e.g.,they display a short-term memory when tumbling and rely on active steering during runs to achieve mechanotaxis,probably via the responses of mechanosensitive ion *** differences reflect the sharp contrast between microglia and bacteria cells(eukaryotes ***)and their environments(compact tissue ***).Further analyses suggest that the reported migration dynamics has an optimal search efficiency and is shared among a subset of immune cells(human monocyte and macrophage).This work reveals a fruitful analogy between the locomotion of 2.remote systems and provides a framework for studying immune cells exploring complex environments.

关键词： analogy closer prompt

Total Synthesis and Stereochemical Assignment of Talaroconvolutin A and Talarofuranone: Gram-scale Synthesis of Ferroptosis Inducer Talaroconvolutin A

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chinese Journal of Chemistry 2024年第13期42卷 1509-1514页

作者： ming Yao Wei Yang Jing li Chengyun Huang Jin {2. Sulu Qin Shuzhi liu Xiaolong Yang school of Pharmaceutical sciences South-Central Minzu UniversityWuhanHubei 430074China

The first total synthesis of talaroconvolutin A(1.1 g obtained)and talarofuranone has been achieved using accessible materials(12.steps,7.5%and 8.2.yields,respectively).Convergent routes involved intramolecular Diels-Alder reactions in two approaches for creating the decalin ***,an unprecedented DMP-mediated domino reaction resulted in the deoxy-tetramic acid *** syntheses not only establish the absolute configuration of talaroconvolutin A but also enable further collaborative studies of this typeofferroptosisinducers.

关键词： Natural products Aldehydes Total synthesis Domino reactions Biological activity Antitumor agents Ferroptosis Diels-Alder reaction Talaroconvolutin A

More than just aligning the teeth:Clear aligners with multifunctional prowess

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Nano Research 2024年第8期17卷 7665-7674页

作者： Yang Chen Lei-ming Cao Nian-Nian Zhong Zi-Zhan li lin-lin Bu fang-Yi Huo Hong He State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei Key Laboratory of StomatologySchool and Hospital of StomatologyWuhan UniversityWuhan 430079China Department of Oral and Maxillofacial-Head Neck Oncology School and Hospital of StomatologyWuhan UniversityWuhan 430079China Department of Zhuankou Clinical Branches School and Hospital of StomatologyWuhan UniversityWuhan 430000China Department of Orthodontics School and Hospital of StomatologyWuhan UniversityWuhan 430079China

With the increasing demand for beauty and health,clear aligners(CAs)have been widely applied among patients with ***,patients treated with CAs also face some potential complications,such as demineralization,dental caries,and periodontal *** addition,some patients have additional needs to improve their quality of life,such as bleaching *** order to prevent or solve these problems,the modification of CAs is a promising method because their extensive long-term contact with tooth surfaces makes them ideal devices for implementing adjuvant medical *** this review,we discuss various advanced CAs with medical functions based on the clinical needs of *** far as we know,the additional functions of CAs mainly include antibacterial,remineralization,whitening,and accelerating tooth *** functions are achieved by two major pathways,the combination of CAs with drugs/biomaterials and increasing the capacity or affinity of *** addition,we discuss the current limitations of in vitro experiments which are designed to explore the effectiveness and properties of novel CAs,and the challenges of bringing a multifunctional appliance from proposal to clinical *** the end of this review,we provide insights into the broader prospects for the improvement of CAs.

关键词： advanced clear aligners medical device modification drug delivery system personalized medicine

A chiral fluorescent probe for molecular recognition of basic amino acids in solutions and cells

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chinese Chemical Letters 2024年第10期35卷 364-369页

作者： Chuan-Zhi Ni Ruo-ming li {2.-Qi Zhang Qu-Ao-Wei li Yuan-Yuan Zhu Jie Zeng Shuang-Xi Gu school of Chemistry and Environmental Engineering School of Chemical Engineering&PharmacyPharmaceutical Research InstituteHubei Key Laboratory of Novel Reactor and Green Chemical TechnologyWuhan Institute of TechnologyWuhan 430205China Nanjing Pusheng Biomedical Co. Ltd.Nanjing 210033China

A novel and readily available binaphthyl-based fluorescent probe(S)-1 was designed and synthesized.(S)-1 can be used to not only chemoselectively discriminate 3 basic amino acids out of common amino acids,but also enantioselectively recognize ***,enantioselective imaging of histidine in cells was achieved for the first time by the probe(S)-*** performances endowed it potential application in the chiral analysis of basic amino acids in asymmetric synthesis and cell imaging for diagnosis of diseases caused by racemization of *** magnetic resonance(NMR)and mass spectrometry investigations suggested that different reaction extent of(S)-1 with L/D-histidine and different product structures generated the observed enantioselective fluorescent *** molecular structures and thermodynamic stability of the complexes,formed from(S)-1+Zn2.and enantiomers of histidine,were calculated by Gaussian 16 based on density functional theory(DFT)to validate the above action mechanism.

关键词： Fluorescent probe Chiral recognition Enantioselectivity Chemoselectivity Basic amino acids Cell imaging

Multi-region calcium imaging in freely behaving mice with ultra-compact head-mounted fluorescence microscopes

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National Science Review 2024年第1期11卷 161-173页

作者： Feng Xue Fei li Ke-ming Zhang Lufeng Ding Yang Wang Xingtao Zhao {2. Xu Danke Zhang mingzhai Sun Pak-ming Lau Qingyuan Zhu Pengcheng Zhou Guo-Qiang Bi Department of Precision Machinery and Precision Instruments University of Science and Technology of China Hefei National Laboratory for Physical sciences at the Microscale University of Science and Technology of China Interdisciplinary Center for Brain Information the Brain Cognition and Brain Disease Institute Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Faculty of life and Health sciences Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences school of life {2. University of Science and Technology of China Institute of Semiconductors Chinese Academy of Sciences Department of Modern life sciences and Biotecnology Xiongan Institute of Innovation Xiongan New Area Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions Suzhou Institute for Advanced Research University of Science and Technology of China Institute of Artiflcial Intelligence Hefei Comprehensive National Science Center

To investigate the circuit-level neural mechanisms of behavior, simultaneous imaging of neuronal activity in multiple cortical and subcortical regions is highly desired. Miniature head-mounted microscopes offer the capability of calcium imaging in freely behaving animals. However, implanting multiple microscopes on a mouse brain remains challenging due to space constraints and the cumbersome weight of the ***, we present TINIscope, a Tightly Integrated Neuronal Imaging microscope optimized for electronic and opto-mechanical design. With its compact and lightweight design of 0.43 g, TINIscope enables unprecedented simultaneous imaging of behavior-relevant activity in up to four brain regions in ***-of-concept experiments with TINIscope recorded over 1000 neurons in four hippocampal subregions and revealed concurrent activity patterns spanning across these regions. Moreover, we explored potential multi-modal experimental designs by integrating additional modules for optogenetics, electrical stimulation or local field potential recordings. Overall, TINIscope represents a timely and indispensable tool for studying the brain-wide interregional coordination that underlies unrestrained behaviors.

关键词： miniature microscope multiple sites calcium imaging multimodal integration hippocampus