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Chemical Research in Chinese Universities 2013年第2期29卷 239-244页

作者： sun yun-kai ZHANG Jin LIU Hui-jun HE Li GONG Hang YANG Nian-fa Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education College of Chemistry Xiangtan University Xiangtan 411105 P. R. China School of Chemistry and Chemical Engineering University of South China Hengyang 421001 P. R. China

A simple and efficient protocol was developed for the syntheses of optically active epoxides（2a--2d） via the reactions of epichlorohydrin with organometallic reagents with steric hindrance at low temperature. On this basis, episulfides（3a--3d） were obtained with high e.e. values by the reaction of the corresponding epoxides with NH4SCN. The configuration of thiiranes was opposite to that of the corresponding epoxides. Then, epoxides 2a--2d were anionically polymerized and the poly-R-2a（or poly-S-2a） was proved to keep a stable one-handed helical conforma- tion in solution. The oligomers[degree of polymerization（DP）=2--5] were obtained when the thiiranes（3a, 3b and 3c） were used to polymerize.

关键词： Optical activity Epoxide Episulfide One-handed helicity

Predicting Hurricane Evacuation Decisions with Interpretable Machine Learning Methods

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International Journal of Disaster Risk Science 2024年第1期15卷 134-148页

作者： Yuran sun Shih‑kai Huang Xilei Zhao Department of Civil and Coastal Engineering University of FloridaGainesvilleFL 32611USA Department of Emergency Management and Public Administration Jacksonville State UniversityJacksonvilleAL 36265USA

Facing the escalating effects of climate change,it is critical to improve the prediction and understanding of the hurricane evacuation decisions made by households in order to enhance emergency *** studies in this area often have relied on psychology-driven linear models,which frequently exhibited limitations in *** present study proposed a novel interpretable machine learning approach to predict household-level evacuation decisions by leveraging easily accessible demographic and resource-related predictors,compared to existing models that mainly rely on psychological *** enhanced logistic regression model(that is,an interpretable machine learning approach) was developed for accurate predictions by automatically accounting for nonlinearities and interactions(that is,univariate and bivariate threshold effects).Specifically,nonlinearity and interaction detection were enabled by low-depth decision trees,which offer transparent model structure and robustness.A survey dataset collected in the aftermath of Hurricanes Katrina and Rita,two of the most intense tropical storms of the last two decades,was employed to test the new *** findings show that,when predicting the households’ evacuation decisions,the enhanced logistic regression model outperformed previous linear models in terms of both model fit and predictive *** outcome suggests that our proposed methodology could provide a new tool and framework for emergency management authorities to improve the prediction of evacuation traffic demands in a timely and accurate manner.

关键词： Artifcial Intelligence(AI) Decision-making modeling Hurricane evacuation Interpretable machine learning Nonlinearity and interaction detection

Probabilistic seismic inversion based on physics-guided deep mixture density network

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Petroleum Science 2024年第3期21卷 1611-1631页

作者： Qian-Hao sun Zhao-yun Zong Xin Li National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina Laoshan Laboratory Qingdao266580ShandongChina CNOOC Research Institute Ltd. Beijing100028China

Deterministic inversion based on deep learning has been widely utilized in model parameters *** by logging data,seismic data,wavelet and modeling operator,deterministic inversion based on deep learning can establish nonlinear relationships between seismic data and model ***,seismic data lacks low-frequency and contains noise,which increases the non-uniqueness of the *** conventional inversion method based on deep learning can only establish the deterministic relationship between seismic data and parameters,and cannot quantify the uncertainty of *** order to quickly quantify the uncertainty,a physics-guided deep mixture density network(PG-DMDN)is established by combining the mixture density network(MDN)with the deep neural network(DNN).Compared with Bayesian neural network(BNN)and network dropout,PG-DMDN has lower computing cost and shorter training time.A low-frequency model is introduced in the training process of the network to help the network learn the nonlinear relationship between narrowband seismic data and low-frequency *** addition,the block constraints are added to the PG-DMDN framework to improve the horizontal continuity of the inversion *** illustrate the benefits of proposed method,the PG-DMDN is compared with existing semi-supervised inversion *** synthetic data examples of Marmousi II model are utilized to quantify the influence of forward modeling part,low-frequency model,noise and the pseudo-wells number on inversion results,and prove the feasibility and stability of the proposed *** addition,the robustness and generality of the proposed method are verified by the field seismic data.

关键词： Deep learning Probabilistic inversion Physics-guided Deep mixture density network

Left atrial appendage occluder detachment treated with transthoracic ultrasound combined with digital subtraction angiography guided catcher:A case report

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World Journal of Clinical Cases 2024年第6期12卷 1157-1162页

作者： kai Yu yun-Hua Mei Department of Ultrasound Wuhan Dongxihu District People's HospitaWuhan 430400Hubei ProvinceChina Department of Infectious Diseases Wuhan Dongxihu District People's HospitalWuhan 430400Hubei ProvinceChina

BACKGROUND There are very few cases of cardiac occluder detachment,and it is rare to completely remove the occluder using interventional methods without undergoing thoracotomy surgery after *** case innovatively used ultrasound guidance combined with digital subtraction angiography(DSA)to completely remove the occluder,accumulating some *** SUMMARY The patient underwent left atrial appendage occlusion surgery in our hospital due to atrial *** the surgery,the occluder fell off and became free in the left ventricle,which is very *** innovatively used ultrasound guidance,combined with DSA,and interventional surgery to successfully capture the free occluder using a catcher,completely remove it,and then re implant a new left atrial appendage *** the surgery,the patient recovered very *** The size selection of the occluder is slightly conservative,and the shape of the left atrial appendage opening is irregular.

关键词： Left atrial appendage occluder Detachment Ultrasound combined with digital subtraction angiography Interventional operation Successfully captured Case report

Design of a Bio-inspired,Two-winged,Flapping-wing Micro Air Vehicle with High-lift Performance

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Journal of Bionic Engineering 2024年第3期21卷 1191-1207页

作者： kai Hu Huichao Deng Shengjie Xiao Gongyu Yang Yuhong sun Space Robot Laboratory The School of Mechanical EngineeringBeihang UniversityBeijing100191China

In this paper,we present the development of our latest flapping-wing micro air vehicle(FW-MAV),named Explobird,which features two wings with a wingspan of 195 mm and weighs a mere 25.2 g,enabling it to accomplish vertical take-off and hover *** devised a novel gear-based mechanism for the flapping system to achieve high lift capability and reliability and conducted extensive testing and analysis on the wings to optimise power matching and lift *** Explobird can deliver a peak lift-to-weight ratio of 1.472 and an endurance time of 259 s during hover flight powered by a single-cell LiPo *** the inherent instability of the prototype,we discuss the derivatives of its longitudinal system,underscoring the importance of feedback control,position of the centre of gravity,and increased *** demonstrate the effect of damping enhancement on stability,we also designed a passive stable ***,the vehicle is actively stabilised in roll by adjusting the wing root bars and in pitch through high-authority tail control,whereas yaw is passively *** a series of flight tests,we successfully demonstrate that our prototype can perform vertical take-off and hover flight under wireless *** promising results position the Explobird as a robust vehicle with high lift capability,paving the way towards the use of FW-MAVs for carrying load equipment in multiple tasks.

关键词： Flapping wing Biologically inspired robots Mechanical design Flight dynamics Damping enhancement

Full-domain collaborative deployment method of multiple interference sources and evaluation of its deployment effect

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Defence Technology（防务技术） 2024年第2期32卷 572-595页

作者： Yue Wang Fuping sun Xian Wang Jinming Hao kai Xiao School of Geospatial Information The PLA Information Engineering UniversityZhengzhou 450001HenanChina

This paper realizes the full-domain collaborative deployment of multiple interference sources of the global satellite navigation system(GNSS)and evaluates the deployment effect to enhance the ability to disturb the attacker and the capability to defend the GNSS during navigation *** evaluation indicators for the jamming effect of GNSS suppressive and deceptive jamming sources are first created,their evaluation models are built,and their detection procedures are sorted out,as the basis for determining the deployment *** principles for collaboratively deploying multi-jamming sources are developed to obtain the deployment structures(including the required number,structures in demand,and corresponding positions)of three single interference sources required by collaboratively ***,simulation and hardware-in-loop testing results are presented to determine a rational configuration of the collaborative deployment of multi-jamming sources in the set situation and further realize the full-domain deployment of an interference network from ground,air to *** evaluation indices for the deployment effect are finally developed to evaluate the deployment effect of the proposed configuration and further verify its reliability and rationality.

关键词： Jamming effect Multiple interference sources Collaborative deployment Effect evaluation Defense capability

The Largest Chinese Cohort Study Indicates Homologous Recombination Pathway Gene Mutations as Another Major Genetic Risk Factor for Colorectal Cancer with Heterogeneous Clinical Phenotypes

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Research 2024年第3期6卷 191-203页

作者： yun Xu kai Liu Cong Li Minghan Li Fangqi Liu Xiaoyan Zhou Menghong sun Megha Ranganathan Liying Zhang Sheng Wang Xin Hu Ye Xu Department of Colorectal Surgery Fudan University Shanghai Cancer CenterShanghaiP.R.China Department of Pathology Fudan University Shanghai Cancer CenterShanghaiP.R.China Department of Pathology Tissue BankFudan University Shanghai Cancer CenterShanghaiP.R.China Department of Medicine Memorial Sloan Kettering Cancer CenterNew YorkNYUSA Department of Pathology and Laboratory Medicine David Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA Precision Cancer Medical Center Fudan University Shanghai Cancer CenterShanghaiP.R.China

While genetic factors were associated with over 30% of colorectal cancer (CRC) patients, mutations in CRC-susceptibility genes were identified in only 5% to 10% of these patients. Besides, previous studies on hereditary CRC were largely designed to analyze germline mutations in patients with single genetic high-risk factor, which limited understanding of the association between genotype and phenotypes. From January 2015 to December 2018, we retrospectively enrolled 2,181 patients from 8,270 consecutive CRC cases, covering 5 categories of genetic high-risk factors. Leukocyte genomic DNA was analyzed for germline mutations in cancer predisposition genes. The germline mutations under each category were detected and analyzed in association with CRC susceptibility, clinical phenotypes, and prognoses. A total of 462 pathogenic variants were detected in 19.3% of enrolled CRC patients. Mismatch repair gene mutation was identified in 9.1% of patients, most prevalent across all high-risk groups. Homologous recombination (HR) gene mutations were detected in 6.5% of cases, penetrated in early-onset and extra-colonic cancer risk groups. Mutations in HR genes, including BARD1, RAD50, and ATM, were found to increase CRC risk with odds ratios of 2.8-, 3.1-, and 3.1-fold, respectively. CRC patients with distinct germline mutations manifested heterogeneous phenotypes in clinicopathology and long-term prognoses. Thus, germline mutation screenings should be performed for CRC patients with any of those genetic risk factors. This study also reveals that HR gene mutations may be another major driver for increased CRC risk.

关键词： susceptibility category Major

Enhancing photodynamic inactivation via tunning spatial constraint on photosensitizer

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Science China Chemistry 2024年第2期67卷 652-663页

作者： Chong Li Minghao Han Ji Gao Shuxian Wang Song-Bo Lu Yaxi Li Zhao Liu Chen Zhang Zhaojin Wang Fangliang Wang Yuang sun Chun Loong Ho kai Wang yun Shen kai Li Shenzhen Key Laboratory of Smart Healthcare Engineering Guangdong Provincial Key Laboratory of Advanced BiomaterialsDepartment of Biomedical EngineeringSouthern University of Science and TechnologyShenzhen518055China Department of Chemical and Environmental Engineering University of California RiversideRiverside92521USA Department of Electrical and Electronic Engineering Southern University of Science and TechnologyShenzhen518055China

The critical factor of spatial constraint,provided by the external confinement(e.g.,matrix),is often overlooked during photodynamic inactivation,despite playing a crucial role in determining the molecular photophysical process and subsequent antipathogen ***,as a proof-of-concept model,we employed two types of polymers with varying interaction energies with dopants to investigate the intrinsic relationship between spatial constraint and the essential excited-state behaviors of doped photosensitizer(4-(2-(5-(4-(diphenylamino)phenyl)thiophen-2-yl)ethyl)-1-methylquinolin-1-ium iodine,TPP).Through experimental investigation and theoretical calculations,we found that TPP tends to remain in the excited state for a shorter dwell time under weaker spatial constraints due to less restricted molecular motion in polyurethane(PU) ***,the singlet oxygen(^(1)O_(2)) generated from doped-TPP shows a 9.23-fold enhancement in PU than in the polyvinylchloride(PVC) *** light irradiation,the PU@TPP nanofiber can efficiently eliminate the coronavirus MHV-A59(≥99.9997%) at a 220,000-fold higher concentration than the infected *** antibacterial efficacy has also been demonstrated,with a killing rate of ≥99%.

关键词： photodynamic antibacterial singlet oxygen triphenylamine nanofiber

Optimized Selection Method of Air Combat Course of Action under Stochastic Uncertainty

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 494-518页

作者： yun Zhong Jieyong Zhang Peng sun Lujun Wan Kepeng Wang Information and Navigation College Air Force Engineering UniversityXi’an710077China Equipment Management and Unmanned Aerial Vehicle Engineering College Air Force Engineering UniversityXi’an710051China Air Traffic Control and Navigation College Air Force Engineering UniversityXi’an710051China Unit 94040 of PLA Korla841000China

Aiming at the design problem of aviation swarm combat course of action(COA),considering the influence of stochastic parameters in the causal relationship model and optimization problem model,according to the dynamic influence net(DIN)theory,stochastic simulation technique,feedforward neural network(FNN)function approximation technique and multi-objective artificial fish school algorithm(MOAFSA),this paper proposed a COA optimized method based on DIN and multi-objective stochastic chance constraint optimization for aviation swarm ***,on the basis of establishing the overall framework of the model and defining the elements of causal relationship modeling,the static and dynamic causal relationship modeling and optimization problem modeling were carried out ***,the probability propagation mechanism of DIN was established,which mainly included two aspects,i.e.,the overall process and the specific ***,input and output data were generated based on stochastic *** to these data,FNN was adopted for function approximation,and MOAFSA was adopted for iterative ***,the rationality of the model,and the effectiveness and superiority of the algorithm were verified through multiple sets of simulation cases.

关键词： Stochastic uncertainty aviation swarm stochastic simulation course of action feedforward neural network multi-objective artificial fish school algorithm

Inbreeding and genetic load in a pair of sibling grouse species:Tetrastes sewersowi and ***

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Avian Research 2024年第2期15卷 265-270页

作者： kai Song Tom van der Valk Bin Gao Peter Halvarsson yun Fang Wendong Xie Siegfried Klaus Zhiming Han Yue-Hua sun Jacob Hoglund Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing100101China Animal Ecology Department of Ecology and GeneticsUppsala UniversityNorbyvagen 18DUppsala75236Sweden Department of Cell and Molecular Biology Uppsala75273Sweden Unit of Parasitology Department of Biomedicine and Veterinary Public HealthSwedish University of Agricultural SciencesPO Box 7036Uppsala75007Sweden Lindenhohe 5 JenaD-07749Germany The State Key Laboratory of Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing100101China

Genetic load and inbreeding are recognized as important factors to be considered in conservation *** levels of both can increase the risk of population extinction by negatively impacting fitness-related characters in many species of plants and animals,including humans(inbreeding depression).Genomic tech-niques are increasingly used in measuring and understanding genetic load and inbreeding and their importance in evolution and *** used whole genome resequencing data from two sibling grouse species in subarctic Eurasia to quantify *** found a large range of inbreeding measured as FROH(fraction of runs of homozygosity)in individuals from different populations of Chinese Grouse(Tetrastes sewerzowi)and Hazel Grouse(***).FROH estimated from genome-wide runs of homozygosity(ROH)ranged from 0.02 to 0.24 among Chinese Grouse populations and from 0.01 to 0.44 in Hazel *** from a population of Chinese Grouse residing in the Qilian mountains and from the European populations of Hazel Grouse(including samples from Sweden,Germany and Northeast Poland)were the most inbred(FROH ranged from 0.10 to 0.23 and 0.11 to 0.44,respectively).These levels are comparable to other highly inbred populations of *** Grouse from northern China and Chinese Grouse residing in the Qinghai-Tibetan Plateau showed relatively lower inbreeding *** of the ratio between deleterious missense mutations and synonymous mutations revealed higher levels in Chinese Grouse as compared to Hazel *** results are possibly explained by higher fixation rates,mutational melt down,in the range-restricted Chinese Grouse compared to the wide-ranging Hazel ***,when we compared the relatively more severe class of loss-of-function muta-tions,Hazel Grouse had slightly higher levels than Chinese Grouse,a result which may indicate that purifying selection(purging)has been more efficient in Chinese Grouse on this class of mutations.

关键词： Genetic load Inbreeding Purifying selection Qinghai-Tibetan Plateau ROH Tetrastes