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Multi-sensor multispectral reconstruction framework based on projection and reconstruction

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Science China(Information Sciences) 2024年第3期67卷 246-262页

作者： Tianshuai li Tianzhu liU xian li Yanfeng GU Yukun WANG Yushi CHeN School of electronics and Information engineering Harbin Institute of Technology Heilongjiang Province Key Laboratory of Space-Air-Ground Integrated Intelligent Remote Sensing

The scarcity and low spatial resolution of hyperspectral images(HSIs) have become a major problem limiting the application of the images. In recent years, spectral reconstruction(SR) has been applied to convert multispectral images(MSIs) with abundant quantities and high spatial resolution into HSIs. With the launch of several new multispectral(MS) satellites with a short repeat period, the simultaneous acquisition of images from multiple MS sensors in the same area is gradually becoming feasible. Unfortunately, existing SR methods only consider the reconstruction of the MSIs of a single sensor without considering using MSIs from different MS sensors to obtain a better construction effect through their complementary bands. However,multi-sensor SR is characterized by two problems: inconsistency in the amplitude information of real multisensor imaging and difficulty in the extraction of the complex correlations of bands from different sensors.To solve these problems, this paper proposes a multi-sensor SR framework based on a two-step approach in which the problems of amplitude inconsistency and band information extraction are solved using an ideal projection network and an ideal multi-sensor SR network, respectively. The effectiveness of the proposed method is verified by experiments on three datasets.

关键词： spectral reconstruction spectral superresolution hyperspectral image multispectral image neural networks multi-sensor

Incidence and risk factors of depression in patients with metabolic syndrome

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World Journal of Psychiatry 2024年第2期14卷 245-254页

作者： li-Na Zhou xian-Cang Ma Wei Wang Department of Psychiatry The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina

BACKGROUND Many studies have explored the relationship between depression and metabolic syndrome(MetS),especially in older people.China has entered an aging society.However,there are still few studies on the elderly in Chinese communities.AIM To investigate the incidence and risk factors of depression in MetS patients in China's Mainland and to construct a predictive model.MeTHODS Data from four waves of the China Health and Retirement Longitudinal Study were selected,and middle-aged and elderly patients with MetS(n=2533)were included based on the first wave.According to the center for epidemiological survey-depression scale(CeSD),participants with MetS were divided into depression(n=938)and non-depression groups(n=1595),and factors related to depression were screened out.Subsequently,the 2-,4-,and 7-year follow-up data were analyzed,and a prediction model for depression in MetS patients was constructed.ReSULTS The prevalence of depression in middle-aged and elderly patients with MetS was 37.02%.The prevalence of depression at the 2-,4-,and 7-year follow-up was 29.55%,34.53%,and 38.15%,respectively.The prediction model,constructed using baseline CeSD and Physical Self-Maintenance Scale scores,average sleep duration,number of chronic diseases,age,and weight had a good predictive effect on the risk of depression in MetS patients at the 2-year follow-up(area under the curve=0.775,95%confidence interval:0.750-0.800,Pensitivity of 68%and a specificity of 74%.CONCLUSION The prevalence of depression in middle-aged and elderly patients with MetS has increased over time.The early identification of and intervention for depressive symptoms requires greater attention in MetS patients.

关键词： Depression Metabolic syndrome Prevalence Risk factor

Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu Yang li Yu liu Xiao-Xiao ling li-Guang Wu li Yang Lan Yang Bo Yang Yong-Gang Zhao xian-Hua li State Key Laboratory of lithospheric evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of earth and Planetary Science University of Chinese Academy of Sciences Ministry of education Key Laboratory of Orogenic Belts and Crustal evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(Ree) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on Ree enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in Ree deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

Upgrading waste NO_(x) into amino acids via electrocatalysis on Co nanoparticles encapsulated in hollow carbon nanofibers

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Science China Chemistry 2024年第6期67卷 1946-1952页

作者： Jiahui xian Kaixing Cai Peisen liao Shihan Wang Guangqin li Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of education LIFMIGCMESchool of ChemistrySun Yat-Sen UniversityGuangzhou510275China

electrocatalytic conversion of waste nitrogen oxide(NO_(x))into value-added nitrogenous chemicals,especially amino acid,is an emerging strategy to alleviate NO_(x)pollution.However,this process suffers from the coexistence of multiple competitive reactions leading to complex product distribution and low efficiency,and thus the rational design and modulation of efficient catalysts remains a formidable challenge.Herein,well-designed Co nanoparticles encapsulated in hollow carbon nanofiber(CoHCNF)were constructed to promote the amino acid electrosynthesis via dealing waste NO_(x)coupling with biomass-derived keto acids.Ascribed to the rapid reactant diffusion,electron transport and efficient contact with abundant accessible Co catalytic sites stemmed from the unique hollow nanotubular structure,Co-HCNF manifested impressive glycine synthesis performance in one-pot adopting NO as the nitrogen source with Faradaic efficiency(Fe)of 41.7%and a corresponding yield rate of 222.3μmol h^(-1)as well as 120 h robust stability.Interestingly,it also demonstrates an excellent performance with the Fe of 42.8%for NO_(3)~-solution as the nitrogen source.Specially,this strategy displays a broad universality for the synthesis of other amino acids.This work not only highlights the importance of hollow-structuring electrocatalyst towards upgrading wasted NO_(x)species into amino acids,but also promotes the further development of electrosynthetic systems for high-valued N-containing organic chemicals.

关键词： electrocatalysis NO_(x)reduction amino acid porous materials hollow structure

Different mechanisms underlie similar species-area relationships in two tropical archipelagoes

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Plant Diversity 2024年第2期46卷 238-246页

作者： Shengchun li Tieyao Tu Shaopeng li xian Yang Yong Zheng liang-Dong Guo Dianxiang Zhang lin Jiang Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China eCNU-Alberta Joint Lab for Biodiversity Study Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China School of Biological Sciences Georgia Institute of TechnologyAtlantaGA 30332USA Jiangxi Academy of Forestry Nanchang 330032China Institute of eco-Chongming(IeC) Shanghai 202162China State Key Laboratory of Biocontrol School of EcologySun Yat-sen UniversityGuangzhou 510275China School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

Despite much research in the field of island biogeography,mechanisms regulating insular diversity remain elusive.Here,we aim to explore mechanisms underlying plant species-area relationships in two tropical archipelagoes in the South China Sea.We found positive plant species-area relationships for both coral and continental archipelagoes.However,our results showed that different mechanisms contributed to similar plant species-area relationships between the two archipelagoes.For coral islands,soil nutrients and spatial distance among communities played major roles in shaping plant community structure and species diversity.By contrast,the direct effect of island area,and to a lesser extent,soil nutrients determined plant species richness on continental islands.Intriguingly,increasing soil nutrients availability(N,P,K)had opposite effects on plant diversity between the two archipelagoes.In summary,the habitat quality effect and dispersal limitation are important for regulating plant diversity on coral islands,whereas the passive sampling effect,and to a lesser extent,the habitat quality effect are important for regulating plant diversity on continental islands.More generally,our findings indicate that island plant species-area relationships are outcomes of the interplay of both niche and neutral processes,but the driving mechanisms behind these relationships depends on the type of islands.

关键词： Coral and continental islands Plant diversity Soil nutrients Species-area relationships The sampling effect

Plants affect the horizontal transmission of a new densovirus infecting the green peach aphid Myzus persicae by modulating honeydew production

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Insect Science 2024年第1期31卷 236-254页

作者： Ya Guo Yani Zhao Yang Yang Yahong Zhang Yuying li Honggang Tian Tong-xian liu Zhaofei li State Key Laboratory of Crop Stress Biology for Arid Areas Key Laboratory of Northwest Loess Plateau Crop Pest Management of Ministry of AgricultureCollege of Plant ProtectionNorthwest A&F UniversityYanglingChina Institute of entomology and Institute of Plant Health&Medicine Guizhou UniversityGuiyangChina

In a tritrophic context of plant-insect-entomopathogen,plants play important roles in modulating the interaction of insects and their pathogenic viruses.Currently,the influence of plants on the transmission of insect viruses has been mainly studied on baculoviruses and some RNA viruses,whereas the impact of plants on other insect viruses is largely unknown.Here,we identified a new densovirus infecting the green peach aphid Myzus persicae and tested whether and how host plants influence the transmission of the aphid densovirus.The complete single-stranded DNA genome of the virus,M.persicae densovirus 2,is 5727 nt and contains inverted terminal repeats.Transcription and phylogenetic analysis indicated that the virus was distinct from other a few identified aphid densoviruses.The virus abundance was detected highly in the intestinal tract of aphids,compared with the lower level of it in other tissues including head,embryo,and epidermis.Cabbage and pepper plants had no obvious effect on the vertical transmission and saliva-mediated horizontal transmission of the virus.However,the honeydew-mediated horizontal transmission among aphids highly depended on host plants(65%on cabbages versus 17%on peppers).Although the virus concentration in the honeydew produced by aphids between 2 plants was similar,the honeydew production of the infected aphids reared on peppers was dramatically reduced.Taken together,our results provide evidence that plants influence the horizontal transmission of a new densovirus in an aphid population by modulating honeydew secretion of aphids,suggesting plants may manipulate the spread of an aphid-pathogenic densovirus in nature.

关键词： aphids densovirus host plants MpDV2 Myzus persicae transmission

Hybrid vibration isolation optimization of a flexible manipulator based on neural network agent model

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Chinese Journal of Aeronautics 2024年第5期37卷 482-505页

作者： Yongxin ZHANG liang li Dingguo ZHANG Wei-Hsin liAO xian GUO School of Science Nanjing University of Science and TechnologyNanjing 210094China Department of Mechanical and Automation engineering The Chinese University of Hong KongHong KongChina

Segmented Active Constrained Layer Damping(SACLD)is an intelligent vibration-damping structure,which could be applied to the sectors of aviation,aerospace,and transportation engineering to reduce the vibration of flexible structures.Moreover,machine learning technology is widely used in the engineering field because of its efficient multi-objective optimization.The dynamic simulation of a rotational segmental flexible manipulator system is presented,in which enhanced active constrained layer damping is carried out,and the neural network model of Genetic Algorithm-Back Propagation(GA-BP)algorithm is investigated.Vibration suppression and structural optimization of the SACLD manipulator model are studied based on vibration mode and damping prediction.The modal responses of the SACLD manipulator model at rest and rotation are obtained.In addition,the four model indices are optimized using the GA-BP neural network:axial incision size,axial incision position,circumferential incision size,and circumferential incision position.Finally,the best model for vibration suppression is obtained.

关键词： Machine learning Vibration suppression Flexible manipulator Segmented active constrained layer damping Structural optimization

Preface to special issue on celebrating the 100th anniversary of Xinjiang University

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Nano Research 2024年第1期17卷 1-4页

作者： Dianzeng Jia Ruimao Hua xian-He Bu Yuliang li State Key Laboratory of Chemistry and Utilization of Carbon Based energy Resources College of ChemistryXinjiang UniversityUrumqi 830017China Department of Chemistry Tsinghua UniversityBeijing 100084China School of Materials Science and engineering Nankai UniversityTianjin 300350China CAS Key Laboratory of Organic Solids Institute of ChemistryChinese Academy of SciencesBeijing 100190China

Xinjiang University originated from Xinjiang College of Russian Language,Political Science and Law in 1924.In 1935 and 1960,the college was re-organized and re-named as Xinjiang College and Xinjiang University,respectively.In 1978,Xinjiang University was appointed by the State Council as the only national key university in Xinjiang.In 1997,it was designated as one of the first batch of key construction universities in the“211 Project”of China.In 2000,Xinjiang University was rebuilt through merging with Xinjiang Institute of Technology.

关键词： Xinjiang anniversary originated

Scattering of Water Waves by Dual Symmetric Inclined Floating Porous Barriers Using the DBeM

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China Ocean engineering 2024年第1期38卷 156-168页

作者： WANG li-xian DeNG Yan-wen Ye Yang-sha DeNG Zheng-zhi Key Laboratory of High Performance Ship Technology(Wuhan University of Technology) Ministry of EducationWuhan 430063China School of Naval Architecture Ocean and Energy Power EngineeringWuhan University of TechnologyWuhan 430063China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha 410114China Institute of Port Coastal and Offshore EngineeringZhejiang UniversityZhoushan 316021China

The scattering of normally incident water waves by two surface-piercing inclined perforated barriers in water with a uniform finite depth is investigated within the framework of linear water wave theory.Considering that thin barriers are zero-thickness,a novel numerical method involving the the coupling of the dual boundary element method(DBeM)with damping layers is applied.In order to effectively damp out the reflected waves,two damping layers,instead of pseudoboundaries are implemented near the two side boundaries of the computational domain.Thus,the modified linearized free surface boundary conditions are formulated and used for solving both the ordinary boundary integral equation as well as the hypersingular boundary integral equation for degenerate boundaries.The newly developed numerical method is validated against analytical methods using the matched eigenfunction expansion method for the special case of two vertical barriers or the inclined angle to the vertical being zero.The influence of the length of the two damping layers has been discussed.Moreover,these findings are also validated against previous results for several cases.After validation,the numerical results for the reflection coefficient,transmission coefficient and dissipation coefficient are obtained by varying the inclination angle and porosity-effect parameter.The effects of both the inclination angle and the porosity on the amplitudes of wave forces acting on both the front and rear barriers are also investigated.It is found that the effect of the inclination angle mainly shifts the location of the extremal values of the reflection and the transmission coefficients.Additionally,a moderate value of the porosity-parameter is quite effective at dissipating wave energy and mitigating the wave loads on dual barriers.

关键词： dual boundary element method inclined perforated floating breakwater reflection coefficient transmission coefficient damping layer