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Quantum-mechanical effects in photoluminescence from thin crystalline gold films

Light(Science & Applications) 2024年第4期13卷 783-794页

作者： Alan R.Bowman Alvaro Rodríguez Echarri Fatemeh Kiani Fadil Iyikanat Ted V.Tsoulos Joel D.Cox Ravishankar Sundararaman F.Javier García de Abajo Giulia Tagliabue Laboratory of Nanoscience for Energy technologies(LNET) STIÉcole Polytechnique Fédérale de Lausanne(EPFL)LausanneSwitzerland ICFO–Institut de Ciencies Fotoniques The Barcelona Institute of Science and TechnologyCastelldefels(Barcelona)Spain. MBI–Max-Born-Institut BerlinGermany. POLIMA–Center for Polariton-driven Light–Matter Interactions University of Southern DenmarkOdense MDenmark. Danish Institute for Advanced Study University of Southern DenmarkOdense MDenmark. Department of Materials Science&Engineering Rensselaer Polytechnic InstituteTroyNYUSA. Department of Physics Applied Physicsand AstronomyRensselaer Polytechnic InstituteTroyNYUSA. ICREA–Institucio Catalana de Recerca i Estudis Avancats BarcelonaSpain

Luminescence constitutes a unique source of insight into hot carrier processes in metals,including those in plasmonic nanostructures used for sensing and energy ***,being weak in nature,metal luminescence remains poorly understood,its microscopic origin strongly debated,and its potential for unraveling nanoscale carrier dynamics largely ***,we reveal quantum-mechanical effects in the luminescence emanating from thin monocrystalline gold ***,we present experimental evidence,supported by first-principles simulations,to demonstrate its photoluminescence origin(i.e.,radiative emission from electron/hole recombination)when exciting in the interband *** model allows us to identify changes to the measured gold luminescence due to quantum-mechanical effects as the gold film thickness is ***,such effects are observable in the luminescence signal from flakes up to 40 nm in thickness,associated with the out-of-plane discreteness of the electronic band structure near the Fermi *** qualitatively reproduce the observations with first-principles modeling,thus establishing a unified description of luminescence in gold monocrystalline flakes and enabling its widespread application as a probe of carrier dynamics and light-matter interactions in this *** study paves the way for future explorations of hot carriers and charge-transfer dynamics in a multitude of material systems.

关键词： luminescence quantum crystalline

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Optical study of magnetic topological insulator MnBi_(4)Te_7

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Chinese Physics B 2024年第1期33卷 231-235页

作者：廖知裕沈冰邱祥冈许兵 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 State Key Laboratory of Optoelectronic Materials and technologies School of PhysicsSun Yat-Sen UniversityGuangzhou 510275China Songshan Lake Materials Laboratory Dongguan 523808China

We present an infrared spectroscopy study of the magnetic topological insulator MnBi_(4)Te_7 with antiferromagnetic(AFM) order below the Neel temperature TN= 13 K. Our investigation reveals that the low-frequency optical conductivity consists of two Drude peaks, indicating a response of free carriers involving multiple bands. Interestingly, the narrow Drude peak grows strongly as the temperature decreases, while the broad Drude peak remains relatively unchanged. The onset of interband transitions starts around 2000 cm^(-1), followed by two prominent absorption peaks around 10000 cm^(-1) and 20000 cm^(-1). Upon cooling, there is a notable transfer of spectral weight from the interband transitions to the Drude response. Below TN, the AFM transition gives rise to small anomalies of the charge response due to a band *** findings provide valuable insights into the interplay between magnetism and the electronic properties in MnBi_(4)Te_7.

关键词： infrared spectroscopy magnetic topological insulator Drude model band reconstruction

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Vision, application scenarios, and key technology trends for 6G mobile communications

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Science China(Information Sciences) 2022年第5期65卷 5-31页

作者： Zhiqin WANG Ying DU Kejun WEI Kaifeng HAN Xiaoyan XU Guiming WEI Wen TONG Peiying ZHU Jianglei MA Jun WANG Guangjian WANG Xueqiang YAN Jiying XIANG He HUANG Ruyue LI Xinhui WANG Yingmin WANG Shaohui SUN Shiqiang SUO Qiubin GAO Xin SU China Academy of Information and Communications Technology Huawei technologies Canada Co. Ltd. Huawei technologies Co. Ltd.(Hangzhou) Huawei technologies Co. Ltd.(Chengdu) Huawei technologies Co. Ltd.(Shanghai) ZTE Corporation Datang Mobile Communications Equipment Co. Ltd.

With the global commercialization of the fifth-generation(5G) network, many countries, including China, USA, European countries, Japan, and Korea, have started exploring 6G mobile communication network, following the tradition of “planning the next while commercializing one generation”. Currently,studies on 6G networks are at the infancy stage. Research on the vision and requirements for 6G is still ongoing, and the industry is yet to clarify the key enabling technologies for 6G. However, 6G will certainly build on the success of 5G. Therefore, developing high-quality 5G networks and seamlessly integrating 5G with verticals are the priorities before 2030, when 6G is projected to be commercialized. Also, global 5G standards will keep evolving to better support vertical applications. As a milestone, the Third-Generation Partnership Project(3GPP) published Release 16 in July 2020, which continuously enhanced the capabilities of mobile broadband service based on Release 15 and realized the support for low-delay and high-reliability applications, such as Internet of Vehicles and industrial Internet. Currently, 3GPP is working on Releases 17 and 18, focusing on meeting the demands of medium-and high-data-rate machine communication with low-cost and high-precision positioning, which will be published in June 2022. Thus, 6G networks will further expand the application fields and scope of the Internet of Things to accommodate those services and applications that are beyond the capabilities of 5G networks. Herein, we present our vision, application scenarios,and key technological trends for 6G networks. Furthermore, we propose several future research opportunities in 6G networks with regard to industrialization and standardization.

关键词： sixth-generation (6G) mobile communication holographic radio technology 6G vision application scenarios of 6G terahertz communication integrated sensing and communication integrated intelligence and communication ultra-massive MIMO reconfigurable intelligent surface co-frequency co-time full-duplex

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New guidance for using t-SNE:Alternative defaults,hyperparameter selection automation,and comparative evaluation

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Visual Informatics 2022年第2期6卷 87-97页

作者： Robert Gove Lucas Cadalzo Nicholas Leiby Jedediah M.Singer Alexander Zaitzeff Two Six technologies USA

We present new guidelines for choosing hyperparameters for t-SNE and an evaluation comparing these guidelines to current *** guidelines include a proposed empirically optimum guideline derived from a t-SNE hyperparameter grid search over a large collection of data *** also introduce a new method to featurize data sets using graph-based metrics called scagnostics;we use these features to train a neural network that predicts optimal t-SNE hyperparameters for the respective data *** neural network has the potential to simplify the use of t-SNE by removing guesswork about which hyperparameters will produce the best *** evaluate and compare our neural network-derived and empirically optimum hyperparameters to several other t-SNE hyperparameter guidelines from the literature on 68 data *** hyperparameters predicted by our neural network yield embeddings with similar accuracy as the best current t-SNE *** our empirically optimum hyperparameters is simpler than following previously published guidelines but yields more accurate embeddings,in some cases by a statistically significant *** find that the useful ranges for t-SNE hyperparameters are narrower and include smaller values than previously reported in the ***,we also quantify the potential for future improvements in this area:using data from a grid search of t-SNE hyperparameters we find that an optimal selection method could improve embedding accuracy by up to two percentage points over the methods examined in this paper.

关键词： Dimensionality reduction Machine learning t-SNE

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Percutaneous Coronary Intervention in Acute Coronary Syndromes at the Mother-Child University Hospital Luxembourg in Bamako

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World Journal of Cardiovascular Diseases 2024年第4期14卷 288-294页

作者： Mamadou Toure Hamma Sankare Baba I. Diarra Mariam Dagnogo Modibo Doumbia Abdoul W. Terra Samba Sidibe Coumba A. Thiam Boubacar Sonfo Boubacar Diarra Asmaou Keita Ousmane Traore Daouda Fofana Almou A. Diall Mady Sow Massama Konate Hamidou O. Ba Ichaka Menta Cardiology Department CHU-Mother Child Bamako Mali Cardiology Department CHU-Gabriel Tour&#233 Bamako Mali Faculty of Medicine University of Sciences Techniques and Technologies of Bamako Bamako Mali Department of Cardiac Surgery Center Andre FESTOC Bamako Mali Cardiology Department CHU-Point G Bamako Mali

Introduction: Acute coronary syndromes (ACS) are a diagnostic and therapeutic emergency. Objective: Studying the feasibility, difficulties and results of coronary angioplasty in acute coronary syndromes at the Luxembourg Mother-Child University Hospital in Bamako. Patients and Methods: Cross-sectional, descriptive study with prospective recruitment over 18 months from September 2020 to February 2022. All patients aged at least 18 years old admitted for SCA and having undergone PCI during the study period were included. Result: We collected 249 patients for SCA, of whom 160 underwent angioplasty, either an angioplasty/SCA ratio of 0.64. The average age of the patients was 59.54 ± 11.62 with extremes of 32 and 92 years. The age group of 45 to 65 years was the most representative. The predominance was male, sex ratio of 2.4. The main cardiovascular risk factors were high blood pressure (58.23%) and diabetes (45.78%). Persistent ST-segment elevation on the electrocardiogram was present in 71.48%. The treatment time was more than 12 hours after the first medical contact in 95.5%. The approach was radial in 96.5% of cases. Coronarography was pathological in 91.16% of our patients. The lesions were tri-truncular in 34.13% with the anterior inter ventricular as culprit artery in 72% of cases. The majority of patients (64%) had undergone angioplasty with implantation of an active stent. Angioplasty was performed successfully in 98% and per procedural mortality was 1.87%. Only 6.45% of ACS with ST elevation benefited from primary angioplasty. Conclusion: Percutaneous coronary intervention is performed routinely in our center with satisfactory results. Difficulties exist, related to the diagnostic delay of ACS and the high cost of angioplasty.

关键词： Acute Coronary Syndromes Coronary Angiography Angioplasty Mother-Child University Hospital Luxembourg Bamako Mali

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Privacy Enhanced Mobile User Authentication Method Using Motion Sensors

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 3013-3032页

作者： Chunlin Xiong Zhengqiu Weng Jia Liu Liang Gu Fayez Alqahtani Amr Gafar Pradip Kumar Sharma Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen518052China Sangfor technologies Inc. Shenzhen518055China School of Data Science and Artificial Intelligence Wenzhou University of TechnologyWenzhou325035China College of Computer Science&Technology Zhejiang University of TechnologyHangzhou310023China Software Engineering Department College of Computer and Information SciencesKing Saud UniversityRiyadh12372Saudi Arabia Math&Computer Science Department Faculty of ScienceMenofia UniversityShebin El-KomEgypt Computing Science Department University of AberdeenAberdeenUK

With the development of hardware devices and the upgrading of smartphones,a large number of users save privacy-related information in mobile devices,mainly smartphones,which puts forward higher demands on the protection of mobile users’privacy *** present,mobile user authenticationmethods based on humancomputer interaction have been extensively studied due to their advantages of high precision and non-perception,but there are still shortcomings such as low data collection efficiency,untrustworthy participating nodes,and lack of *** this end,this paper proposes a privacy-enhanced mobile user authentication method with motion sensors,which mainly includes:(1)Construct a smart contract-based private chain and federated learning to improve the data collection efficiency of mobile user authentication,reduce the probability of the model being bypassed by attackers,and reduce the overhead of data centralized processing and the risk of privacy leakage;(2)Use certificateless encryption to realize the authentication of the device to ensure the credibility of the client nodes participating in the calculation;(3)Combine Variational Mode Decomposition(VMD)and Long Short-TermMemory(LSTM)to analyze and model the motion sensor data of mobile devices to improve the accuracy of model *** experimental results on the real environment dataset of 1513 people show that themethod proposed in this paper can effectively resist poisoning attacks while ensuring the accuracy and efficiency of mobile user authentication.

关键词： Mobile authentication blockchain federated learning smart contract certificateless encryption VMD LSTM

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Development of a multicellular 3D-bioprinted microtissue model of human periodontal ligament-alveolar bone biointerface:Towards a pre-clinical model of periodontal diseases and personalized periodontal tissue engineering

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Genes & Diseases 2022年第4期9卷 1008-1023页

作者： Murat Taner Vurat ŞükranŞeker Özge Lalegül-Ülker Mahmut Parmaksiz Ayşe Eser Elçin Yaşar Murat Elçin Tissue Engineering Biomaterials and Nanobiotechnology LaboratoryAnkara University Faculty of ScienceAnkara University Stem Cell InstituteAnkara 06100Turkey Biovalda health technologies Inc.Ankara 06100Turkey

While periodontal (PD) disease is among principal causes of tooth loss worldwide, regulation of concomitant soft and mineralized PD tissues, and PD pathogenesis have not been completely clarified yet. Besides, relevant pre-clinical models and in vitro platforms have limitations in simulating human physiology. Here, we have harnessed three-dimensional bioprinting (3DBP) technology for developing a multi-cellular microtissue model resembling PD ligament-alveolar bone (PDL-AB) biointerface for the first time. 3DBP parameters were optimized;the physical, chemical, rheological, mechanical, and thermal properties of the constructs were assessed. Constructs containing gelatin methacryloyl (Gel-MA) and hydroxyapatite-magnetic iron oxide nanoparticles showed higher level of compressive strength when compared with that of Gel-MA constructs. Bioprinted self-supporting microtissue was cultured under flow in a microfluidic platform for >10 days without significant loss of shape fidelity. Confocal microscopy analysis indicated that encapsulated cells were homogenously distributed inside the matrix and preserved their viability for >7 days under microfluidic conditions. Immunofluorescence analysis showed the cohesion of stromal cell surface marker-1+ human PDL fibroblasts containing PDL layer with the osteocalcin+ human osteoblasts containing mineralized layer in time, demonstrating some permeability of the printed constructs to cell migration. Preliminary tetracycline interaction study indicated the uptake of model drug by the cells inside the 3D-microtissue. Also, the non-toxic levels of tetracycline were determined for the encapsulated cells. Thus, the effects of tetracyclines on PDL-AB have clinical significance for treating PD diseases. This 3D-bioprinted multi-cellular periodontal/osteoblastic microtissue model has potential as an in vitro platform for studying processes of the human PDL.

关键词： 3D bioprinting Alveolar bone Microtissue model Organ-on-a-chip .Periodontal ligament Periodontal tissue engineering Periodontal-osteoblastic biointer face Periodontium-on-a-chip

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基于创新性内侧壁成型工艺的多光学通道微型碱金属原子气室

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Engineering 2024年第4期35卷 46-55页

作者： Mingzhi Yu Yao Chen Yongliang Wang Xiangguang Han Guoxi Luo Libo Zhao Yanbin Wang Yintao Ma Shun Lu Ping Yang Qijing Lin Kaifei Wang Zhuangde Jiang International Joint Laboratory for Micro/Nano Manufacturing and Measurement technologies Xi’an Jiaotong UniversityXi’an 710049China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing Yantai 265503China Moon Environment Technology Co. Ltd.Yantai 264000China Emergency Department The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061China

Existing microfabricated atomic vapor cells have only one optical channel,which is insufficient for supporting the multiple orthogonal beams required by atomic *** this study,we present a novel wafer-level manufacturing process for fabricating multi-optical-channel atomic vapor cells and an innovative method for batch processing the inner sidewalls of millimeter glass holes to meet optical channel *** characterization and transmittance tests demonstrate that the processed inner sidewalls satisfy the criteria for an optical *** addition,the construction of an integrated processing platform enables multilayer non-isothermal anode bonding,the filling of inert gases,and the recovery and recycling of noble *** of the absorption spectra and free-induction decay signals of xenon-129(^(129)Xe)and xenon-131(^(131)Xe)under different pump-probe schemes demonstrate the suitability of our vapor cell for use in atomic devices including atomic gyroscopes,dual-beam atomic magnetometers,and other optical/atomic *** proposed micromolding technology has broad application prospects in the field of optical-device processing.

关键词： Microfabricated atomic vapor cells Inner-sidewall molding Multiple optical channels Quantum sensing

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Epileptic brain network mechanisms and neuroimaging techniques for the brain network

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Neural Regeneration Research 2024年第12期19卷 2637-2648页

作者： Yi Guo Zhonghua Lin Zhen Fan Xin Tian Department of Neurology Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Sichuan Provincial Center for Mental health Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Department of Geriatrics Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Department of Neurology Chongqing Key Laboratory of NeurologyThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina

Epilepsy can be defined as a dysfunction of the brain network,and each type of epilepsy involves different brain-network changes that are implicated diffe rently in the control and propagation of interictal or ictal *** more detailed information on brain network alterations can help us to further understand the mechanisms of epilepsy and pave the way for brain network-based precise therapeutic approaches in clinical *** increasing number of advanced neuroimaging techniques and electrophysiological techniques such as diffusion tensor imaging-based fiber tra ctography,diffusion kurtosis imaging-based fiber tractography,fiber ball imagingbased tra ctography,electroencephalography,functional magnetic resonance imaging,magnetoencephalography,positron emission tomography,molecular imaging,and functional ultrasound imaging have been extensively used to delineate epileptic *** this review,we summarize the relevant neuroimaging and neuroelectrophysiological techniques for assessing structural and functional brain networks in patients with epilepsy,and extensively analyze the imaging mechanisms,advantages,limitations,and clinical application ranges of each technique.A greater focus on emerging advanced technologies,new data analysis software,a combination of multiple techniques,and the construction of personalized virtual epilepsy models can provide a theoretical basis to better understand the brain network mechanisms of epilepsy and make surgical decisions.

关键词： electrophysiological techniques epilepsy functional brain network functional magnetic resonance imaging functional near-infrared spectroscopy machine leaning molecular imaging neuroimaging techniques structural brain network virtual epileptic models

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Mechanisms of resistance to trastuzumab in HER2-positive gastric cancer

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Chinese Journal of Cancer Research 2024年第3期36卷 306-321页

作者： Zhifei Li Huan Zhao Huihui Hu Haili Shang Yongjing Ren Wenhui Qiu Hao Su Huifang Lyu Xiaobing Chen Department of Oncology the Affiliated Cancer Hospital of Zhengzhou University&Henan Cancer HospitalHenan Engineering Research Center of Precision Therapy of Gastrointestinal CancerZhengzhou Key Laboratory for Precision Therapy of Gastrointestinal CancerZhengzhou 450008China Henan University of Traditional Chinese Medicine Zhengzhou 450046China State Key Laboratory of Esophageal Cancer Prevention&Treatment Key Laboratory of Advanced Drug Preparation TechnologiesMinistry of EducationSchool of Pharmaceutical SciencesZhengzhou UniversityZhengzhou 450001China The First Affiliated Hospital of Xinxiang Medical University Xinxiang 453000China Department of Oncology the Affiliated Cancer Hospital of Zhengzhou University&Henan Cancer HospitalZhengzhou 450008China

Gastric cancer is one of the most prevalent cancers worldwide,and human epidermal growth factor receptor 2(HER2)-positive cases account for approximately 20%of the total ***,trastuzumab+chemotherapy is the recommended first-line treatment for patients with HER2-positive advanced gastric cancer,and the combination has exhibited definite efficacy in HER2-targeted ***,the emergence of drug resistance during treatment considerably reduces its effectiveness;thus,it is imperative to investigate the potential mechanisms underlying *** the present review article,we comprehensively introduce multiple mechanisms underlying resistance to trastuzumab in HER2-positive gastric cancer cases,aiming to provide insights for rectifying issues associated with resistance to trastuzumab and devising subsequent treatment strategies.

关键词： HER2 gastric cancer trastuzumab drug resistance

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