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Prediction of synchronous colorectal cancers by computed tomography in subjects receiving an incomplete colonoscopy:A single-center study

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World Journal of Gastroenterology 2015年第6期21卷 1857-1864页

作者： Er-Jun Pang wei-Jie Liu Jia-Yuan Peng ni-wei chen Jian-Hong Deng Department of Surgery the Sixth People's Hospital Affiliated to Shanghai Jiao Tong University Center of Endoscopy the Sixth People's Hospital Affiliated to Shanghai Jiao Tong University Department of Radiology the Sixth People's Hospital Affiliated to Shanghai Jiao Tong University

AIM:To assess the value of computed tomography(CT)for diagnosis of synchronous colorectal cancers(SCRCs)involving incomplete ***:A total of 2123 cases of colorectal cancer(CRC)were reviewed and divided into two groups according to whether a complete or incomplete colonoscopy was *** results and final histological findings were compared to calculate the sensitivity and specificity associated with CT for detection of SCRCs following complete vs incomplete *** affecting the CT detection were also ***:Three hundred and seventy-four CRC patients underwent incomplete colonoscopy and 1749received complete ***-six cases of SCRCs were identified by CT,and 36 were *** the incomplete colonoscopy group,the sensitivity and specificity of CT were 44.8%and 93.6%,*** positive and negative predictive values were 23.6%and 95.0%,*** contrast,the sensitivity and specificity of CT for the complete colonoscopy group were 68.3%and 97.0%,while the positive and negative predictive values were 22.2%and 98.7%,*** both groups,the mean maximum dimension of the concurrent cancers identified in the CT-negative cases was shorter than in the CT-positive cases(incomplete group:P=0.02;complete group:Pnitored.

关键词： Synchronous colorectal cancer Computed tomography

Ceramic-based meta-material absorber with high-temperature stability

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Rare Metals 2024年第9期43卷 4433-4440页

作者： Xing-Cong chen wei-Jia Luo Run-ni Zhao Yong-Zheng Wen Ji Zhou State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

With the continuous exploration of uncharted and extreme environments,enhanced temperature robustness of passive devices has become particularly *** this study,a ceramic-based meta-material absorber with exceptional temperature stability is developed using a fusion design approach that combines rare metal-based tungsten bronze structural ceramics and ***,the absorbance of the meta-material array based on Mie resonance exceeds 49.0%in both waveguides and free space,approaching the theoretical *** to impedance analysis,the absorption performance can be distinctly correlated with the dielectric loss(Q_(f)).Notably,the high-temperature robustness is verified to still be effective at 400℃.These advancements in our design allow for the use of monolithic materials in fabricating temperature-stable perfect absorbers,providing greater freedom in the dielectric performance and expanding their potential applications,including in space exploration and 5G millimeter-wave scenarios.

关键词： Temperature robustness Meta-material absorber Microwave absorption Rare metal-based ceramics Miniaturization

Rotation forest based on multimodal genetic algorithm

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Journal of Central South University 2021年第6期28卷 1747-1764页

作者： XU Zhe ni wei-chen JI Yue-hui School of Electrical and Electronic Engineering Tianjin University of TechnologyTianjin 300384China Academic Affairs Office Tianjin University of TechnologyTianjin 300384China Tianjin Key Laboratory for Control Theory&Applications in Complicated Industry Systems Tianjin 300384China

In machine learning,randomness is a crucial factor in the success of ensemble learning,and it can be injected into tree-based ensembles by rotating the feature ***,it is a common practice to rotate the feature space ***,a large number of trees are required to ensure the performance of the ensemble *** random rotation method is theoretically feasible,but it requires massive computing resources,potentially restricting its applications.A multimodal genetic algorithm based rotation forest(MGARF)algorithm is proposed in this paper to solve this *** is a tree-based ensemble learning algorithm for classification,taking advantage of the characteristic of trees to inject randomness by feature ***,this algorithm attempts to select a subset of more diverse and accurate base learners using the multimodal optimization *** classification accuracy of the proposed MGARF algorithm was evaluated by comparing it with the original random forest and random rotation ensemble methods on 23 UCI classification *** results show that the MGARF method outperforms the other methods,and the number of base learners in MGARF models is much fewer.

关键词： ensemble learning decision tree multimodal optimization genetic algorithm

Biodegradation of Pentachloronitrobenzene by Labrys portucalensis pcnb-21 Isolated from Polluted Soil

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Pedosphere 2011年第1期21卷 31-36页

作者： LI Rong ZHENG Jin-wei ni Bin chen Kai YANG Xiu-Juan LI Shun-Peng JIANG Jian-Dong Key Laboratory of Microbiological Engineering of Agricultural Environment Ministry of Agriculture College of Life Sciences Nanjing Agricultural University Nanjing 210095 (China)

A bacterial strain, pcnb-21, capable of degrading pentaehloronitrobenzene （PCNB） under aerobic and anoxic conditions, was isolated from a long-term PCNB-polluted soil by an enrichment culture technique and identified as Labrys portucalensis based upon its morphological, physiological and biochemical properties, as well as 16S rRNA gene sequence analysis. Effects of different factors, such as temperature and pH, on PCNB biodegradation were studied. Strain pcnb-21 efficiently degraded PCNB at temperatures from 20 to 30 ℃ and initial pH values from 4 to 7, which might be the first time that a Labrys strain was found capable of eflClciently degrading PC1NB. The degradation of PCNB was affected by oxygen, and the degradation decreased with increasing aeration. Exogenous electron donors such as glucose, lactic acid and succinic acid promoted the biodegradation of PCNB, while electron acceptors such as sodium nitrite, sodium sulfate, sodium nitrate and sodium sulfate inhibited PCNB biodegradation. The degradation of PCNB in sterile and non-sterile soils by a green fluorescent protein （GFP）-labeled strain, pcnb-21-gfp, was also studied. Cells of pcnb-21-gfp efficiently degraded 100 mg kg-1 PCNB in sterile and non-sterile soils and could not be detected after 42 days. Strain pcnb-21 might be useful in bioremediating PCNB-polluted soils and environment.

关键词： aeration bacterial strain electron acceptors electron donors sterile soil

Light-induced stepped thermal relaxation in a Hofmann-type metal-organic framework

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Science China Chemistry 2024年第6期67卷 1983-1989页

作者： Wen Cui wei-wei Wu Ze-Yu Ruan Yan-Cong chen Guang-Jun Zeng Guan-Xi chen Si-Guo Wu Zhao-Ping ni Ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistryInstitute of Green Chemistry and Molecular EngineeringGuangdong Basic Research Center of Excellence for Functional Molecular EngineeringSun Yat-sen UniversityGuangzhou510275China

Spin-crossover(SCO)materials with light-induced multistability have potential applications in multi-addressable opto-magnetic memory devices and multiple ***,we reported a three-dimensional Hofmann-type metal-organic framework(MOF)[Fe(bpy){Pt(CN)_(4)}]·coumarin(1·coumarin,bpy=4,4′-bipyridine),which exhibits an incomplete and hysteretic SCO *** importantly,the light-induced stepped thermal relaxation(LISTR)with obvious magnetic plateau for a hidden intermediate spin state is firstly *** hidden spin state is also observed for the first time in the thermal relaxation after light-assisted spin state annealing(LASSA).Meanwhile,an extremely rare bi-directional light-induced excited spin-state trapping(LIESST)with the highest reverse-LIESST temperature is ***,five spin states can be captured in 1·coumarin and the tristability can be modulated below 102 K through the excitation-relaxation ***,the light-and temperatureinduced multistability provides a new strategy for developing multistable materials.

关键词： light magnetic multistability iron metal-organic framework spin-crossover

Classification of aviation incident causes using LGBM with improved cross-validation

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Journal of Systems Engineering and Electronics 2024年第2期35卷 396-405页

作者： ni Xiaomei WANG Huawei chen Lingzi LIN Ruiguan School of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Aeronautical Engineering Nanjing Vocational University of Industry TechnologyNanjing 210023China

Aviation accidents are currently one of the leading causes of significant injuries and deaths worldwide. This entices researchers to investigate aircraft safety using data analysis approaches based on an advanced machine learning *** assess aviation safety and identify the causes of incidents, a classification model with light gradient boosting machine (LGBM)based on the aviation safety reporting system (ASRS) has been developed. It is improved by k-fold cross-validation with hybrid sampling model (HSCV), which may boost classification performance and maintain data balance. The results show that employing the LGBM-HSCV model can significantly improve accuracy while alleviating data imbalance. Vertical comparison with other cross-validation (CV) methods and lateral comparison with different fold times comprise the comparative approach. Aside from the comparison, two further CV approaches based on the improved method in this study are discussed:one with a different sampling and folding order, and the other with more CV. According to the assessment indices with different methods, the LGBMHSCV model proposed here is effective at detecting incident causes. The improved model for imbalanced data categorization proposed may serve as a point of reference for similar data processing, and the model’s accurate identification of civil aviation incident causes can assist to improve civil aviation safety.

关键词： aviation safety imbalance data light gradient boosting machine(LGBM) cross-validation(CV)

Energy-efficient joint UAV secure communication and 3D trajectory optimization assisted by reconfigurable intelligent surfaces in the presence of eavesdroppers

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Defence Technology（防务技术） 2024年第1期31卷 537-543页

作者： Huang Hailong Mohsen Eskandari Andrey V.Savkin wei ni The Department of Aeronautical and Aviation Engineering The Hong Kong Polytechnic UniversityHong KongChina School of Electrical Engineering and Telecommunications University of New South WalesSydney2052Australia Data61 CSIROAustralia

We consider a scenario where an unmanned aerial vehicle(UAV),a typical unmanned aerial system(UAS),transmits confidential data to a moving ground target in the presence of multiple *** friendly reconfigurable intelligent surfaces(RISs) help to secure the UAV-target communication and improve the energy efficiency of the *** formulate an optimization problem to minimize the energy consumption of the UAV,subject to the mobility constraint of the UAV and that the achievable secrecy rate at the target is over a given *** present an online planning method following the framework of model predictive control(MPC) to jointly optimize the motion of the UAV and the configurations of the *** effectiveness of the proposed method is validated via computer simulations.

关键词： Unmanned aerial systems(UASs) Unmanned aerial vehicle(UAV) Communication security Eaves-dropping Reconfigurable intelligent surfaces(RIS) Autonomous navigation and placement Path planning Model predictive control

Transjugular intrahepatic portosystemic shunt:A promising therapy for recompensation in cirrhotic patients

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World Journal of Gastroenterology 2024年第16期30卷 2285-2286页

作者： Ya-ni Jin wei Zhang Department of Gastroenterology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjing 210000Jiangsu ProvinceChina

This is a retrospective study focused on recompensation after transjugular intrahepatic portosystemic shunt(TIPS)*** authors confirmed TIPS could be a treatment for recompensation of patients with cirrhosis according to Baveno *** paper identified age and post-TIPS portal pressure gradient as independent predictors of recompensation in patients with decompensated cirrhosis after *** results need to be validated in a larger prospective cohort.

关键词： Cirrhosis recompensation Transjugular intrahepatic portosystemic shunt Portal pressure gradient Predictor factor Baveno VII

Aerial target threat assessment based on gated recurrent unit and self-attention mechanism

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Journal of Systems Engineering and Electronics 2024年第2期35卷 361-373页

作者： chen chen QUAN wei SHAO Zhuang School of Automation Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing 100081China

Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties in dealing with high dimensional time series target data, a threat assessment method based on self-attention mechanism and gated recurrent unit(SAGRU) is proposed. Firstly, a threat feature system including air combat situations and capability features is established. Moreover, a data augmentation process based on fractional Fourier transform(FRFT) is applied to extract more valuable information from time series situation features. Furthermore, aiming to capture key characteristics of battlefield evolution, a bidirectional GRU and SA mechanisms are designed for enhanced ***, after the concatenation of the processed air combat situation and capability features, the target threat level will be predicted by fully connected neural layers and the softmax classifier. Finally, in order to validate this model, an air combat dataset generated by a combat simulation system is introduced for model training and testing. The comparison experiments show the proposed model has structural rationality and can perform threat assessment faster and more accurately than the other existing models based on deep learning.

关键词： target threat assessment gated recurrent unit(GRU) self-attention(SA) fractional Fourier transform(FRFT)