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Evolution of artificial ion channels

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National Science Review 2024年第1期11卷 72-73页

作者： Yugang Wang School of Physics Peking University

Protein ion channels on a cell membrane generate action potentials for cellular signal transduction, and regulate biological activities during life. Since the discovery of the asymmetric ion transport phenomenon in quartz nanopipettes by Bard and colleagues [1], synthetic nanofluidic materials and devices have attracted a lot of research interests from the scientific community,

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Perception field based imitation learning for unlabeled multi-agent pathfinding

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Science China(Information Sciences) 2024年第5期67卷 115-135页

作者： Wenjie CHU Ailun YU Wei ZHANG Haiyan ZHAO Zhi JIN School of Computer Science Peking University Key Laboratory of High-Confidence Software Technologies (peking university) Ministry of Education

This paper proposes an imitation learning method to learn a universal agent policy for unlabeled multi-agent pathfinding(unlabeled MAPF) in grid environments. The method transforms the unlabeled MAPF problem into a series of temporal-independent homogeneous classification problems for each *** on this transformation, a neural network is designed to imitate a distance-optimal expert *** neural network consists of two successive modules: perception field learner and field integrating *** former refines and encodes the current system state into a perception field for each agent by combining a set of learnable field-generating functions. The latter takes an agent's perception field as input and decides the agent's next action based on a triplet cross-attention mechanism. We evaluate our method on a diverse set of unlabeled MAPF tasks. Compared with state-of-the-art counterparts, the experimental results manifest the superiority of the proposed method in both generalization ability and scalability.

关键词： unlabeled multi-agent pathfinding perception field triplet cross-attention multi-agent imitation learning learning-based planning

Low-thermal-budget synthesis of monolayer MoS2

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Science China Materials 2024年第1期67卷 372-374页

作者： Zongmeng Yang Shibo Fang Jing Lu State Key Laboratory for Mesoscopic Physics and School of Physics Peking University Collaborative Innovation Center of Quantum Matter Beijing Key Laboratory for Magnetoelectric Materials and Devices (BKL-MEMD) Peking University peking university Yangtze Delta Institute of Optoelectronics Key Laboratory for the Physics and Chemistry of Nanodevices Peking University Beijing Key Laboratory of Quantum Devices Peking University

Two-dimensional (2D) materials, such as MoS2, have been considered as a competitive coordinate for future electronics due to their excellent electrostatics and high mobility [1–3]. Moreover, the potential integration of 2D materials with silicon circuits can present increased density and multifunction in future heterogeneously integrated circuits [4,5]. However, the high thermal-budget during Mo S2 synthesis exceeds the temperature requirement of direct integration with Si in the back-end-of-line (BEOL) fabrication process [6–8].

关键词： FILMS

Versatile photonic molecule switch in multimode microresonators

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Light(Science & Applications) 2024年第3期13卷 498-509页

作者： Zihan Tao Bitao Shen Wencan Li Luwen Xing Haoyu Wang Yichen Wu Yuansheng Tao Yan Zhou Yandong He Chao Peng Haowen Shu Xingjun Wang State Key Laboratory of Advanced Optical Communications System and Networks School of ElectronicsPeking UniversityBeijing 100871China College of Engineering Peking UniversityBeijing 100871China School of Integrated Circuits Peking University100871 BejingChina peking university Yangtze Delta Institute of Optoelectronics Nantong 226010China Frontiers Science Center for Nano-optoelectronics Peking UniversityBeijing 100871China Peng Cheng Laboratory Shenzhen 518055China

Harnessing optical supermode interaction to construct artificial photonic molecules has uncovered a series of fundamental optical phenomena analogous to atomic ***,the distinct energy levels and interactions in such two-level systems were provided by coupled *** reconfigurability is limited,as they often require delicate external field stimuli or mechanically altering the geometric *** highly specific approaches also limit potential ***,we propose a versatile on-chip photonic molecule in a multimode microring,utilizing a flexible regulation methodology to dynamically control the existence and interaction strength of spatial *** transition between single/multi-mode states enables the“switched-off/on”functionality of the photonic molecule,supporting wider generalized applications *** particular,“switched-on”state shows flexible and multidimensional mode splitting control in aspects of both coupling strength and phase difference,equivalent to the *** *** effect.“Switched-off”state allows for perfect low-loss single-mode transition(Qi~10 million)under an ultra-compact bend size(FSR~115 GHz)in a foundry-based silicon *** breaks the stereotyped image of the FSR-Q factor trade-off,enabling ultra-wideband and high-resolution millimeter-wave photonic *** demonstration provides a flexible and portable solution for the integrated photonic molecule system,extending its research scope from fundamental physics to real-world applications such as nonlinear optical signal processing and sixth-generation wireless communication.

关键词： switched multimode millimeter

Noncontact ultrasound sensing based on Mach-Zehnder homodyne interferometer for photoacoustic imaging

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Chinese Optics Letters 2024年第3期22卷 101-106页

作者：龙星胡毅成王一冰李长辉 Department of Biomedical Engineering College of Future TechnologyPeking UniversityBeijing 100871China National Biomedical Imaging Center Peking UniversityBeijing 100871China

We present a novel noncontact ultrasound(US)and photoacoustic imaging(PAI)system,overcoming the limitations of traditional coupling *** a long coherent length laser,we employ a homodyne free-space Mach-Zehnder setup with zero-crossing triggering,achieving a noise equivalent pressure of 703 Pa at 5 MHz and a-6 dB bandwidth of 1 to8.54 *** address the phase uncertainty inherent in the homodyne *** the noncontact US probe enables photoacoustic computed tomography(PACT).Phantom studies demonstrate imaging performance and system stability,underscoring the potential of our system for noncontact US sensing and PAI.

关键词： noncontact ultrasound sensing photoacoustic imaging Mach–Zehnder interferometer

Curcumin Interferes with TGF-β1-Induced Fibrosis in NRK-49F Cells by Reversing ADAMTS18 Gene Methylation

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Chinese Journal of Integrative Medicine 2024年第7期30卷 600-607页

作者： XU Ben ZHANG Jia-en YE Lin YUAN Chang-wei Department of Urology Peking University First Hospital and Institute of UrologyPeking UniversityNational Urological Cancer CenterBeijing100034China

Objective To explore the molecular mechanism by which curcumin affects renal interstitial fibrosis(RIF)progression by regulating ADAM metallopeptidase with thrombospondin type 1 motif 18(ADAMTS18)*** NRK-49F cells RIF model were induced with transforming growth factorβ1(TGF-β1).Effects of different concentrations of curcumin(0,10,20,and 30μmol/L)on cell proliferation,cell cycle,cell apoptosis as well as cyclin D1 expression were analyzed by cell counting kit-8,flow cytometry and Western blot,***18 methylation levels were determined by methylation-specific polymerase chain ***18,fibronectin(FN),type I collagen(Col-I)and alpha-smooth muscle actin(α-SMA)mRNA and protein expressions were analyzed by real-time PCR(RT-PCR)and Western blot,***,cells were treated with 50 mmol/L 5-aza-2′-deoxycytidine(5-aza-dC,demethylation agent)for 72 *** of curcumin on extracellular matrix(ECM)deposition was evaluated by immunochemical staining and Western ***-49F cells were transfected with ADAMTS18 small interfering RNA and grouped into a normal control,ADAMTS18-knock-out(KO),and ADAMTS18-KO+30μmol/L curcumin groups,and whether curcumin can reverse the effect of ADAMTS18 knockdown on RIF was *** Compared with the control group,TGF-β1 significantly inhibited the proliferation of NRK-49F cells,blocked the G1/G0 phase,promoted cell apoptosis and inhibited cyclin D1 expression(P<0.01).Among the different concentrations of curcumin,30μmol/L curcumin significantly reversed these processes(P<0.01).Immunochemical staining and Western blot results showed that curcumin significantly inhibited the deposition of FN,Col-I andα-SMA(P<0.01).Curcumin and 5-zaz-dC had synergistic effects,promoting ADAMTS18 expression,removing ADAMTS18 methylation,and reducing ECM ***18 knockdown promoted ECM accumulation,and curcumin reversed this process(P<0.01).Conclusion TGF-β1-induced fibrosis in NRK-49F ***

关键词： renal fibrosis curcumin Chinese medicine ADAMTS18 methylation modification

A historical overview of nano-optics:from near-field optics to plasmonics

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Chinese Physics B 2024年第5期33卷 134-145页

作者：邓妙怡朱星 Department of History of Science Technology and MedicineAcademy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China School of Physics Peking UniversityBeijing 100871China

Nano-optics is an emergent research field in physics that appeared in the 1980s,which deals with light–matter optical interactions at the nanometer *** early studies of nano-optics,the main concern focus is to obtain higher optical resolution over the diffraction *** researches of near-field imaging and spectroscopy based on scanning near-field optical microscopy(SNOM)are *** exploration of improving SNOM probe for near-field detection leads to the emergence of surface *** the sense of resolution and wider application,there has been a significant transition from seeking higher resolution microscopy to plasmonic near-field modulations in the nano-optics community during the nano-optic ***,studies of nano-optics prefer the investigation of plasmonics in different material *** this article,the history of the development of near-field optics is briefly *** difficulties of conventional SNOM to achieve higher resolution are *** an alternative solution,surface plasmons have shown the advantages of higher resolution,wider application,and flexible nano-optical modulation for new *** typical studies in different periods are introduced and characteristics of nano-optics in each stage are *** this way,the evolution progress from near-field optics to plasmonics of nano-optics research is *** future development of nano-optics is discussed then.

关键词： nano-optics near-field optics surface plasmon plasmonic modulation

Targeting LTA4H facilitates the reshaping of the immune microenvironment mediated by CCL5 and sensitizes ovarian cancer to Cisplatin

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Science China(Life Sciences) 2024年第6期67卷 1226-1241页

作者： Zhengyang Guo Jiaqi Huang Xiao Huo Chen Huang Xiaotong Yu Yan Sun Yanfang Li Tianhui He Hongyan Guo Jianling Yang Lixiang Xue Cancer Center of peking university Third Hospital Beijing 100191China Center of Basic Medical Research Institute of Medical Innovation and ResearchPeking University Third HospitalBeijing 100191China peking university Third Hospital Cancer Center Department of Radiation OncologyPeking University Third HospitalBeijing 100191China Department of Obstetrics and Gynecology Peking University Third HospitalBeijing 100191China

Ovarian cancer is the most lethal and aggressive gynecological cancer with a high recurrence rate and is often diagnosed *** ovarian cancer,multiple metabolic enzymes of lipid metabolism are abnormally expressed,resulting in metabolism *** a characteristic pathway in polyunsaturated fatty acid(PUFA)metabolism,arachidonic acid(AA)metabolism is disturbed in ovarian ***,we established a 10-gene signature model to evaluate the prognostic risk of PUFA-related *** 10-gene signature has strong robustness and can play a stable predictive role in datasets of various platforms(TCGA,ICGC,and GSE17260).The high association between the risk subgroups and clinical characteristics indicated a good performance of the *** data further indicated that the high expression of LTA4H was positively correlated with poor prognosis in ovarian *** of LTA4H enhanced sensitivity to Cisplatin and modified the characteristics of immune cell infiltration in ovarian ***,our results indicate that CCL5 was involved in the aberrant metabolism of the AA/LTA4H axis,which contributes to the reduction of tumor-infiltrating CD8+T cells and immune escape in ovarian *** findings provide new insights into the prognosis and potential target of LTA4H/CCL5 in treating ovarian cancer.

关键词： ovarian cancer polyunsaturated fatty acids prognostic risk model LTA4H tumor immunity CCL5

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Establishment of a cholangiocarcinoma risk evaluation model based on mucin expression levels

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1344-1360页

作者： Chun-Yuan Yang Li-Mei Guo Yang Li Guang-Xi Wang Xiao-Wei Tang Qiu-Lu Zhang Ling-Fu Zhang Jian-Yuan Luo Department of Pathology Institute of Systems BiomedicineSchool of Basic Medical Sciences Peking UniversityPeking University Third HospitalPeking University Health Science CenterBeijing 100191China Department of General Surgery Peking University Third HospitalBeijing 100191China Department of Medical Genetics Department of Biochemistry and BiophysicsSchool of Basic Medical Sciences Peking UniversityPeking University Health Science CenterBeijing 100191China

BACKGROUND Cholangiocarcinoma(CCA)is a highly malignant cancer,characterized by frequent mucin ***1 has been identified as a critical oncogene in the progression of ***,the comprehensive understanding of how the mucin family influences CCA progression and prognosis is still *** To investigate the functions of mucins on the progression of CCA and to establish a risk evaluation formula for stratifying CCA *** Single-cell RNA sequencing data from 14 CCA samples were employed for elucidating the roles of mucins,complemented by bioinformatic ***-quent validations were conducted through spatial transcriptomics and *** construction of a risk evaluation model utilized the least absolute shrinkage and selection operator regression algorithm,which was further confirmed by independent cohorts and diverse data *** CCA tumor cells with elevated levels of MUC1 and MUC4 showed activated nucleotide metabolic pathways and increased ***5AC-high cells were found to promote CCA progression through WNT ***5B-high cells exhibited robust cellular oxidation activities,leading to resistance against antitumoral ***13-high cells were observed to secret chemokines,recruiting and transforming macrophages into the M2-polarized state,thereby suppressing antitumor ***16-high cells were found to promote tumor progression through interleukin-1/nuclear factor kappa-light-chain-enhancer of activated B cells signaling upon interaction with *** the expression levels of these mucins,a risk factor evaluation formula for CCA was developed and validated across multiple *** samples with higher risk factors exhibited stronger metastatic potential,chemotherapy resistance,and poorer *** Our study elucidates the functional mechanisms through which mucins contribute to CCA development,and provides tools for risk stratification in CCA.

关键词： Mucin Cholangiocarcinoma Single-cell RNA sequencing Spatial transcriptomics Prognosis