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Underground Space 2024年第6期19卷 279-300页

作者： Weiping luo Dajun Yuan Yannick Choy Hing ng Dalong Jin Ping Lu Teng Wang Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of the Ministry of Education for Urban Underground Engineering Beijing Jiaotong UniversityBeijing 100044China Department of Civil and Environmental Engineering National University of SingaporeSingapore 119077Singapore

Many empirical and analytical methods have been proposed to predict fracturing pressure in cohesive *** of them take into account three to four specific influencing factors and rely on the assumption of a failure *** this study,a novel data-mining approach based on the XGBoost algorithm is investigated for predicting fracture initiation in cohesive *** has the advantage of handling multiple influencing factors simultaneously,without pre-determining a failure mode.A dataset of 416 samples consisting of 14 distinct features was herein collected from past studies,and used for developing a regressor and a classifier model for fracturing pressure prediction and failure mode classification *** results show that the intrinsic characteristics of the soil govern the failure mode while the fracturing pressure is more sensitive to the stress *** XGBoost-based model was also tested against conventional approaches,as well as a similar machine learning algorithm namely random forest ***,several large-scale triaxial fracturing tests and an in-situ case study were carried out to further verify the generalization ability and applicability of the proposed data mining approach,and the results indicate a superior performance of the XGBoost model.

关键词： Fracturing pressure Failure mode Cohesive soil Data-mining Large-scale tests

Synthesis of an AIE-active fluorogen and its application in cell imaging

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Science China Chemistry 2009年第1期52卷 15-19页

作者： LAM Jacky Wing Yip FAISAL Mahtab ng Ka Ming luo Kathy Qian Department of Chemistry The Hong Kong University of Science & Technology (HKUST) Clear Water Bay Department of Chemical and Biomolecular Engineering HKUST Clear Water Bay Bioengineering Graduate Program HKUST Clear Water Bay

A fluorogen named 1-decyl-1-methyl-2,5-bis{4-[(N,N-diethylamino)methyl]phenyl}-3,4-diphenylsilole (3) was synthesized. It emitted weakly as isolated molecule but strongly as supramolecular aggregate, showing a characteristic behavior of aggregation-induced emission (AIE). The molecules of 3 formed highly emissive nanoparticles in aqueous media, which quickly and selectively marked cytoplasm of HeLa cells and posed no toxicity to the living cells. The fluorogen is thus a promising candidate mate-rial for cell imaging as a sensitive, selective and cytocompatible biosensor.

关键词： aggregation-induced emission biosensor cell imaging

Calibration of the Solar X-ray Detector on-board the Macao Science Satellite-1B for Soft X-ray Detection

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Science China Earth Sciences 2025年第1期 11-26页

作者： Man-Hei ng Xiaoping ZHAng Jianwu CHEN Yongqiang SHI Fuchang ZUO Wenxi PEng Weichun FU Liansheng LI Pengwei luo Chi-Long TAng Guozheng ZHAng Zhiwu MEI Li WAng Cunhui LI Jiaming OU Yanyan XU State Key Laboratory of Lunar and Planetary Sciences Macau University of Science and Technology China National Space Administration (CNSA) Macau Center for Space Exploration and Science Space Optoelectronic Measurement and Perception Laboratory Beijing Institute of Control Engineering Institute of High Energy Physics Chinese Academy of Sciences Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of Physics

The Solar X-ray Detector(SXD) on-board the Macao Science Satellite-1B(MSS-1B) was successfully launched via the Chinese Long March-2C rocket on 21 May 2023, and commenced operations in early June of the same year. The MSS-1B/Soft X-ray Detection Units(SXDUs) employ two silicon drift detectors(SDDs), providing a wide range of energy spectra spanning from 0.7 to 24 keV. Notably, the SXDUs deliver a high-resolution capability of 0.14 keV@5.9 keV and operate with a time cadence of 1 second. Here, we perform thorough calibrations of the MSS-1B/SXDUs, employing a combination of ground experiments and simulations. In addition, quantitative analysis comparing the flux measurements obtained by the MSS-1B/SXDUs to the data collected by the Geostationary Operational Environmental Satellite(GOES), provides compelling evidence of their consistency. Furthermore, the preliminary spectral analysis results showcase the robustness and expected performance of the MSS-1B/SXDUs, unlocking their potential for facilitating the study of dynamic evolution of solar flares. Moreover, the innovative MSS-1B/Solar X-ray Detector facilitates concurrent observations of solar soft and hard X-rays, thereby making valuable contributions to the advancements in solar research.

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Inadvertent placement of a urinary catheter into the ureter: A report of 3 cases and review of the literature

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Asian Journal of Urology 2017年第4期4卷 256-261页

作者： Rui luo Song Liang Lee Foo Cheong ng Li-Tsa Koh Department of Urology Changi General HospitalSingapore

We describe three cases of inadvertent placement of the urinary catheter into the *** 85-year-old gentleman on long-term indwelling catheter(IDC)for neurogenic bladder presented with fever and right flank *** of abdomen and pelvis demonstrated the tip of the IDC to be located within the right vesicoureteric junction with acute right hydronephrosis and acute pyelonephritis.A 74-year-old woman,on long-term IDC for neurogenic bladder was found to have hydronephrosis on ultrasound ***-enhanced CT intravenous pyelography done subsequently showed the IDC was in the right distal ureter.A 47-year-old lady,on IDC for urinary retention and voiding dysfunction likely secondary to schizophrenia and anti-psychotic medications,presented with raised creatinine.A non-enhanced CT of her abdomen and pelvis was done and showed that the tip of the urethral IDC was located up to the left vesicoureteric *** all patients,the hydronephrosis resolved after changing the catheter and they were well on *** also review the literature to identify the incidence,outcomes and possible risk *** our knowledge,only 20 cases have been reported thus far in the English *** serious complications can occur,the incidence is very *** risk factor that has been identified is long-term catheterization in patients with neurogenic *** do not recommend routine imaging after catheterization in this group of ***,we should still be mindful of the possibility of this occurrence and evaluate and treat as necessary when clinical suspicion arises.

关键词： Indwelling catheter Ureter Complication

State-to-state Photoionization Dynamics of Vanadium Nitride by Two-color Laser Photoionization and Photoelectron Methods

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Chinese Journal of Chemical Physics 2013年第6期26卷 669-678,I0003页

作者： Huang Huang Zhi-hong luo Yih Chung Chang Kai-Chung Lau C. Y. ng Department of Chemistry University of California Davis CA 95616 USA Department of Biology and Chemistry Oty University of Hone Kong Kowloon Hone Kong China

We have conducted a two-color visible-ultraviolet （VIS-UV） resonance-enhanced laser pho- toionization and pulsed field ionization-photoelectron （PFI-PE） study of gaseous vana- dium mononitride （VN） in the total energy range of 56900-59020 cm-1. The VN molecules were selectively excited to single rotational levels of the intermediate VN（D3H0, v＇=0） state by using a VIS dye laser prior to photoionization by employing a UV laser. This two-color scheme allows the measurements of rovibronically selected and re- solved PFI-PE spectra for the VN＋（X2A; v＋=0, 1, and 2） ion vibrational bands. By simulating the rotationally resolved PFI-PE spectra, J＋=3/2 is determined to be the lowest rotational level of the ground electronic state, indicating that the symmetry of the ground VN＋ electronic state is 2A3/2. The analysis of the PFI-PE spectra for VN＋ also yields accurate values for the adiabatic ionization energy for the formation of VN＋（X2A3/2）, IE（VN）=56909.5＋0.8 cm-1 （7.05588±0.00010 eV）, the vibrational fre- quency wc＋=1068.0±0.8 cm-1, the anharmonicity constant wc＋Xe＋=5.8±0.8 cm-1, the rotational constants Be＋=0.6563±0.0005 cm-1 and ae＋=0.0069±0.0004 cm-1, and the equi-librium bond length, re＋=1.529A, for VN＋（X2A3/2）; along with the rotational constants Bc＋=0.6578i0.0028 cm-1 and a＋=0.0085±0.0028 cm-1, and the equilibrium bond length re＋=1.527A for VN＋（X2As/2）, and the spin-orbit coupling constant A=153.3±0.8 cm-1 for VN＋（X2/k5/2,3/2）. The highly precise energetic and spectroscopic data obtained in the present study are valuable for benchmarking the predictions based on state-of-the-art ab initio quantum calculations.

关键词： Vanadium nitride Vanadium nitride cation Photoionization dynamics Two- color photoionization Pulsed field ionization-photoelectron Ionization energy Bond disso- ciation energy

Genetic Variants in EGFR/PLCE1 Pathway Are Associated with Prognosis of Esophageal Squamous Cell Carcinoma after Radical Resection

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Current Medical Science 2019年第3期39卷 385-390页

作者： Yu-li WAng Ye YUAN Xiao-xiao luo Guang-yuan HU Ping G0ng Department of Oncology the First Affiliated Hospital of the Medical College Shihezi University Shihezi 832008China Department of Clinical Medicine School of Medicine Shihezi University Shihezi 832008China Department of Oncology Tongji HospitalTongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China

Esophageal cancer (EC) is one of the most deadly malignant diseases. Several studies revealed that variations of the phospholipase C epsilon 1 (PLCE1) gene were associated with EC susceptibility. PLCE1 is located downstream of the epidermal growth factor receptor (EGFR) pathway. Presently, the single nucleotide polymorphisms (SNPs) of EGFR/PLCE1 genes and their associations with EC survival remain unclea匚 In this study, the associations between genetic variants in the EGFR/PLCE1 pathway and prognosis in 124 esophageal squamous cell carcinoma (ESCC) patients with radical resection were explored. The results showed that CC genotype of both PLCE1 rsl7109671 and EGFR rs2072454 was associated with ESCC prognosis. Multivariate analysis revealed that patients with the two unfavorable genotypes had the worst overall survival (OS) or disease-free survival (DFS)(HR=6.099, 95%CI=1.903-19.552;HR=3.994, 95%CI=1.49-10.702, respectively). Additionally, combination of SNPs and tumor stage could better predict OS (for AUC, 0.774 vs. 0.709) and PFS (for AUC, 0.773 vs. 0.704) than tumor stage *** conclusion, genetic variants of the EGFR/PLCE1 may be predictors of the prognosis of ESCC after surgery. The individuals with the CC genotype of PLCE1 rsl7109671 and EGFR rs2072454 should receive more aggressive treatments.

关键词： esophageal squamous cell carcinoma prognosis single nucleotide polymorphism survival epidermal growth factor receptor

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口腔鳞癌中染色体9p杂合性丢失的研究

华西口腔医学杂志 2001年第5期19卷 275-277页

作者：肖林 IOL ng ZC luo 四川大学华西医院肿瘤中心 610041 香港大学玛丽医院

目的 :探讨口腔鳞状细胞癌中 9号染色体短臂等位基因的杂合性丢失和微卫星不稳定与口腔鳞状细胞癌发生、发展之间的关系。方法 :采用PCR法检测 2 4例口腔鳞状细胞癌中染色体 9p上 8个微卫星多态位点。结果 :在2 4例口腔鳞状细胞癌中 ,10... 详细信息

目的 :探讨口腔鳞状细胞癌中 9号染色体短臂等位基因的杂合性丢失和微卫星不稳定与口腔鳞状细胞癌发生、发展之间的关系。方法 :采用PCR法检测 2 4例口腔鳞状细胞癌中染色体 9p上 8个微卫星多态位点。结果 :在2 4例口腔鳞状细胞癌中 ,10例 (41 6 7% )鳞癌组织至少有一个微卫星位点发生杂合性丢失。其主要发生在染色体9p2 1的D9S171(2 1 0 5 % )和D9S30 4(10 .0 0 % ) ,以及 9p2 2_2 3的D9S16 8(2 2 2 2 % )和D9S16 2 (15 38% )。然而 ,这些基因位点的杂合性丢失与肿瘤病理学类型、肿瘤的大小及转移性在统计学上无显著相关性 (P >0 0 5 )。此外 ,微卫星不稳定仅在 2例患者中出现 ,没有 1例患者符合微卫星不稳定的判定标准 ,即两个或两个以上的微卫星多态位点的异常。结论 :本研究中发现的口腔鳞状细胞癌在染色体 9p2 1_2 3区域发生高频率的杂合性丢失 ,提示在 9p2 1_2 3区域可能存在多个与部分口腔鳞状细胞癌相关的肿瘤抑制基因。

关键词：口腔鳞癌杂合性丢失染色体9p

Flexible multifunctional platform based on piezoelectric acoustics for human–machine interaction and environmental perception

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Microsystems & Nanoengineering 2022年第5期8卷 91-103页

作者： Qian Zhang Yong Wang Dongsheng Li Jin Xie Ran Tao Jingting luo Xuewu Dai Hamdi Torun Qiang Wu Wai Pang ng Richard Binns YongQing Fu The State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University310027 HangzhouChina Faculty of Engineering and Environment University of NorthumbriaNewcastle upon Tyne NE18STUK Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province School of EngineeringWestlake University310024 HangzhouChina Key Laboratory of Optoelectronic Devices and Systems of Education Ministry and Guangdong Province College of Physics and Optoelectronic EngineeringShenzhen University518060 ShenzhenChina

Flexible human–machine interfaces show broad prospects for next-generation flexible or wearable electronics compared with their currently available bulky and rigid ***,compared to their rigid counterparts,most reported flexible devices(e.g.,flexible loudspeakers and microphones)show inferior performance,mainly due to the nature of their ***,it is of great significance to improve their performance by developing and optimizing new materials,structures and design *** this paper,a flexible acoustic platform based on a zinc oxide(ZnO)thin film on an aluminum foil substrate is developed and optimized;this platform can be applied as a loudspeaker,a microphone,or an ambient sensor depending on the selection of its excitation *** used as a speaker,the proposed structure shows a high sound pressure level(SPL)of~90 dB(with a standard deviation of~3.6 dB),a low total harmonic distortion of~1.41%,and a uniform directivity(with a standard deviation of~4 dB).Its normalized SPL is higher than those of similar devices reported in the recent *** used as a microphone,the proposed device shows a precision of 98%for speech recognition,and the measured audio signals show a strong similarity to the original audio signals,demonstrating its equivalent performance compared to a rigid commercial *** a flexible sensor,this device shows a high temperature coefficient of frequency of−289 ppm/K and good performance for respiratory monitoring.

关键词： acoustics piezoelectric speakers

SHAPE OF POLYMER CHAINS ON A TETRAHEDRAL LATTICE

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Chinese Journal of Polymer Science 2000年第5期18卷 419-422页

作者： Jian-hua Huang Me+ng-bo luo Wen-hua Jiang Shi-jun Han Department of Chemistry, Zhejiang University, Hangzhou 310027, China Department of Physics, Zhejiang University, Hangzhou 310027, China Zhejiang Univ Dept Chem Hangzhou 310027 Peoples R China Zhejiang Univ Dept Phys Hangzhou 310027 Peoples R China

The shape of unperturbed polymer chains was studied using the Monte Carlo technique on a tetrahedral lattice. The asphericity A, the ratios / and / were calculated for different Values of polymer chain length n, conformational energy epsilon (epsilon greater than or equal to 0) and temperature T. The asphericity A decreases with the increase of chain length and tends to reach its limiting value rapidly with the decrease of gamma (gamma = epsilon/k(B)T). For large n, A is about 0.525 +/- 0.005, the ratios / and / are about 2.7 and 12.0, respectively, and are almost independent of gamma, but for short chains, they depend on gamma.

关键词： shape polymer chain Monte Carlo technique

Drag increment induced by a small-scale forward-facing step in Mach number5 turbulent boundary layer flows

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Chinese Journal of Aeronautics 2020年第10期33卷 2491-2498页

作者： Yifei XUE Jie REN Jinling luo Song FU School of Aerospace Engineering Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering University of NottinghamNottingham NG72RDUnited Kingdom Beijing Aerospace Technology Institute Beijing 100074China

Small-scale roughness elements or imperfections are inevitable over the surface of a flight *** aerodynamics of these small-scale structures is difficult to predict but may play an important role in the design of a flight vehicle at high *** forward-facing step is a typical type of roughness *** experiments have been conducted to study the aerodynamics of supersonic forward-facing step,especially with a step height larger than boundary layer ***,few studies focus on small *** improve the understanding of small-scale forwardfacing step flow,we perform a series of simulations to analyze its aerodynamic influence on a Mach number 5 turbulent boundary *** general flow structures are analyzed and *** shock waves can be induced by the step even if the step height is much smaller than the boundary layer *** significant shocks are the separation shock and the reattachment *** influenced area by the step is *** the increase of the step height,the non-dimensional influence area decreases and gradually converges when the step height reaches the boundary layer *** are two normalized distributions of the skin friction coefficient and pressure coefficient associated with step *** using the normalized parameters,a power-law relationship between the step height and the drag increment coefficient is revealed and fits the simulation results *** is further illustrated that this relationship still holds when changing the inlet angle of attack,but needs slight modification with the angle of attack.

关键词： Aerodynamics Drag increment Forward-facing step Hypersonic flow Turbulent boundary layer