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Orbital angular momentum-mediated machine learning for high-accuracy mode-feature encoding

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Light(Science & Applications) 2024年第3期13卷 466-477页

作者： Xinyuan Fang Xiaonan Hu baoli Li Hang Su Ke Cheng Haitao Luan Min Gu Institute of Photonic Chips University of Shanghai for Science and TechnologyShanghai 200093China Centre for Artificial-Intelligence Nanophotonics School of Optical-Electrical and Computer EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China

Machine learning with optical neural networks has featured unique advantages of the information processing including high speed,ultrawide bandwidths and low energy consumption because the optical dimensions(time,space,wavelength,and polarization)could be utilized to increase the degree of ***,due to the lack of the capability to extract the information features in the orbital angular momentum(OAM)domain,the theoretically unlimited OAM states have never been exploited to represent the signal of the input/output nodes in the neural network ***,we demonstrate OAM-mediated machine learning with an all-optical convolutional neural network(CNN)based on Laguerre-Gaussian(LG)beam modes with diverse diffraction *** proposed CNN architecture is composed of a trainable OAM mode-dispersion impulse as a convolutional kernel for feature extraction,and deep-learning diffractive layers as a *** resultant OAM mode-dispersion selectivity can be applied in information mode-feature encoding,leading to an accuracy as high as 97.2%for MNIST database through detecting the energy weighting coefficients of the encoded OAM modes,as well as a resistance to eavesdropping in point-to-point free-space ***,through extending the target encoded modes into multiplexed OAM states,we realize all-optical dimension reduction for anomaly detection with an accuracy of 85%.Our work provides a deep insight to the mechanism of machine learning with spatial modes basis,which can be further utilized to improve the performances of various machine-vision tasks by constructing the unsupervised learning-based auto-encoder.

关键词： polarization mode momentum

CO_2 emission and organic carbon burial in the Xinanjiang Reservoir

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Acta Geochimica 2017年第3期36卷 465-468页

作者： Fushun Wang baoli Wang Tao Zhou Tianyu Chen Jing Ma School of Environmental and Chemical Engineering Shanghai University Institute of Surface-Earth System Science Tianjin University

In order to understand the effect of river impoundment on carbon dynamics, a large reservoir in a subtropical area, the Xinanjiang Reservoir, was investigated in detail. CO_2 emissions from the water–air interface was studied, as was organic carbon burial in sediment. The results show a significant seasonal difference in CO_2 emissions. River impoundment led to the enhancement of aquatic photosynthesis, generating large amounts of authigenic organic carbon that was then buried in sediment.

关键词： The Xinanjiang Reservoir Carbon emission Sediment Carbon retention

Quantum chemical study on the abstraction reaction of alkylidenegermylene with oxirane and thiirane

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Science China Chemistry 2007年第3期50卷 335-344页

作者： GENG ZhiYuan YAO Kun WANG YongCheng FANG Ran ZHANG XingHui JIA baoli Gansu Key Laboratory of Polymer Materials College of Chemistry and Chemical EngineeringNorthwest Normal UniversityLan-zhou 730070China

The mechanisms of the abstraction reaction of alkylidenegermylene with oxirane and thiirane have been characterized detail in using density functional theory, as well as ab initio method, including geometry optimization and vibrational analysis for the involved stationary points on the potential energy surface. Energies were calculated by CCSD(T)/6-311G(d)//B3LYP/6-311G(d,p) method for the involved conformations. The results show that the reaction pathways for both reactions consist of two ways: (1) the reactants can yield bent products (P1; P4) by syn-isomers; (2) the reactants can also yield three-membered products (P2; P5) by anti-isomers, which then further react with oxirane and thiirane to form the ultimate products (P3-1, P3-2; P6). Furthermore, a comparison with alkylidenecarbene, oxirane, and thiirane was done.

关键词： alkylidenegermylene ab initio density functional theory transition state

Of genes and microbes： solving the intricacies in host genomes

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Protein & Cell 2018年第5期9卷 446-461页

作者： Jun Wang Liang Chen Na Zhao Xizhan Xu Yakun Xu baoli Zhu CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of Microbiology Chinese Academy of Science Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Collaborative Innovation Centre for Diagnosis and Treatment of Infectious Diseases First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310058 China

Microbiome research is a quickly developing field in biomedical research, and we have witnessed its poten- tial in understanding the physiology, metabolism and immunology, its critical role in understanding the health and disease of the host, and its vast capacity in disease prediction, intervention and treatment. However, many of the fundamental questions still need to be addressed, including the shaping forces of microbial diversity between individuals and across time. Microbiome research falls into the classical nature vs. nurture sce- nario, such that host genetics shape part of the micro- biome, while environmental influences change the original course of microbiome development. In this review, we focus on the nature, i.e., the genetic part of the equation, and summarize the recent efforts in understanding which parts of the genome, especially the human and mouse genome, play important roles in determining the composition and functions of microbial communities, primarily in the gut but also on the skin. We aim to present an overview of different approaches in studying the intricate relationships between host genetic variations and microbes, its underlying philos- ophy and methodology, and we aim to highlight a few key discoveries along this exploration, as well as current pitfalls. More evidence and results will surely appear in upcoming studies, and the accumulating knowledge will lead to a deeper understanding of what we could finally term a ＂hologenome＂, that is, the orga- nized, closely interacting genome of the host and the microbiome.

关键词： gut microbiota host genetics quantitativegenetics gene-microbiome association

Flux of organic carbon burial and carbon emission from a large reservoir: implications for the cleanliness assessment of hydropower

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Science Bulletin 2019年第9期64卷 603-611页

作者： Fushun Wang Yunchao Lang Cong-Qiang Liu Yong Qin Ningxiao Yu baoli Wang School of Environmental and Chemical Engineering Shanghai University Institute of Surface-Earth System Sciences Tianjin University

Accurately quantifying the budget of carbon sources and sinks in hydropower reservoirs is important for evaluating the cleanliness of hydroelectricity. However, current research on carbon emissions from reservoirs has rarely taken into account the organic carbon(OC) buried in sediment. Only greenhouse gas emissions from the water-air interface at reservoirs have been examined, which would result in an overestimation of the greenhouse effect of reservoirs. In November 2017, this study investigated the distribution of sediment in the Hongfeng Reservoir(HFR) in southwest China, a typical large hydropower reservoir, by using an underwater seismology monitoring system. We estimated the flux of OC into sediment using the results of a sediment survey and a dataset compiled from references. Our results show that, the HFR retained 200,715 t of OC in the sediment since its impounding after dam construction to the sampling year of 2017, when the average burial flux was 3,521 t-C aà1(106 g C aà1) and the modern burial flux was 5,449 t-C aà1. After excluding the exogenous OC, the modern valid carbon sink of the sediment was 4,632 t per year. Under the current state of the reservoir, taking the modern valid carbon sink value, the carbon emissions from the reservoir's surface, and the discharge water from the dam into consideration, the net carbon sink of the HFR is found to be 1,098.9 t-C aà1. If the hydroelectricity generated by the reservoir is converted to a carbon sink, then the total net carbon sink becomes 12,972.9 t-C aà*** work argues that both reservoir sediment and hydroelectricity are important carbon sinks and both should be included in assessments of the greenhouse effects of reservoirs.

关键词： The Hongfeng Reservoir Sediment Carbon sink Underwater seismology method

Comparison of Formation Conditions of Source Rocks of Fengcheng and Lucaogou Formations in the Junggar Basin,NW China:Implications for Organic Matter Enrichment and Hydrocarbon Potential

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Journal of Earth Science 2023年第4期34卷 1026-1040页

作者： Shiju Liu Gang Gao Wenzhe Gang baoli Xiang Ming Wang Chengyun Wang College of Geosciences China University of PetroleumNo.18 Fuxue RoadBeijing 102249China State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumNo.18 Fuxue RoadBeijing 102249China PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China Experimental Testing Institute PetroChina Xinjiang Oilfield CompanyKaramay 834000China Exploration and Development Research Institute of PetroChina Huabei Oilfield Company Renqiu 062552China

Shales in the Carboniferous–Permian Fengcheng(FC) and Lucaogou(LCG) formations in Junggar Basin are important organic rich rocks containing significant oil *** evaluate the difference in sedimentary environment conditions and hydrocarbon-generating potential between the FC and LCG *** organic carbon(TOC),Rock-Eval pyrolysis,solvent extraction,column fractionation,stable carbon isotope,gas chromatography-mass spectrometry(GC-MS) of saturated hydrocarbons and organic petrology from the source rocks of FC and LCG *** *** biomarker composition indicates that during the deposition of FC,LCG-1 to LCG-2,the sedimentary environment for the source rock formations changed with gradual decrease of salinity,from anoxic to dyoxic/suboxic in redox conditions,and from strong stratification to weakened stratification of *** FC Formation source rock,with main telalginite(planktonic green algae),archaebacteria and minor terrestrial organic matter,deposited in the environment characterized by high salinity and strongly reducing *** TOC content is relatively low with a high original hydrocarbongenerating potential of unit organic *** LCG Formation source rock deposited in the environment with low salinity and large variations,the organic matter is mainly sourced from telalginite(planktonic green algae),lamalginite,bacteria and higher plants,resulting in strong heterogeneity of the source *** abundance of TOC is high,but the original hydrocarbon generation potential of unit organic matter is lower than that of FC *** results provide a geochemical basis for further study of saline-brackish water sedimentary environment shales in the Junggar Basin.

关键词： geochemistry biogenic precursors depositional conditions Fengcheng Formation LucaogouFormation JunggarBasin.

Impacts of river impoundment on the riverine water chemistry composition and their response to chemical weathering rate

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Frontiers of Earth Science 2013年第3期7卷 351-360页

作者： Yang GAO baoli WANG Xiaolong LIU Yuchun WANG Jing ZHANG Yanxing JIANG School of Environmental and Chemical Engineering Shanghai University Shanghai 200444 China Institute of Geochemistry Chinese Academy of Science Guiyang 550002 China Tianjin Normal University Tianjin 300387 China Department of Water Environment China Institute of Water Resources and Hydroelectric Power Research (IWHR) Beijing 100038 China

Currently, most rivers worldwide have been intensively impounded. River damming becomes a big problem, not only in inducing the physical obstruction between upstream and downstream, but also in destroying the natural continuity of river. But the discontinuity of water quality was often neglected, which presents a challenge to traditional river geochemistry research. To understand the changes in basic chemistry of water upstream and downstream of the dam, we investigated the Miaotiao River reservoirs in series in the Wujiang River Basin, and the Hongjiadu, Dongfeng Reservoir on the upper reaches of the Wujiang River. Chemical weathering rates were calculated using the water chemistry data of the reservoir surface and downstream of the dam, in each reservoir, respectively. The results showed that the difference between the chemical weathering rates calculated from reservoir surface water and water downstream of the dam was greater in reservoirs with a longer water retention time. In Hongjiadu Reservoir with the longest water retention time among the studied reservoirs, this difference reaches 9%. As a result, the influence of fiver damming, especially the influence of reservoirs in series, should be taken into account when calculating the chemical weathering rate of a fiver basin.

关键词： reservoirs in series chemical weathering rate Wujiang

Developing nutrient criteria for the Jiulong River Estuary,Southeast China

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Acta Oceanologica Sinica 2018年第2期37卷 1-13页

作者： LIU baoli CAO Wenzhi HUANG Zheng CHEN Wenhui CHEN Huihuang LIU Lusan State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361102 China College of the Environment and Ecology Xiamen University Xiamen 361102 China College of Geographical Sciences Fujian Normal University Fuzhou 350007 China Chinese Research Academy of Environmental Sciences Beijing 100012 China

One of the key concerns in estuarine and coastal environments is eutrophication, which is known to be closely connected to nutrient enrichment. To control and improve surface water quality, nutrient criteria are recommended in order to provide reference conditions for the environment. However, the current datasets of nutrient criteria in China are either designed for surface water or sea water, and as such these are not suitable for assessing estuarine water quality, especially given the unique ecosystem and dynamic properties of estuaries. To address this issue in current estuarine water management, nutrient criteria have been developed for a local estuary in the southeast of China. Segmentation of the Jiulong River Estuary, China was firstly analysed through field investigations carried out during 2013–2014, which resulted in the delineation of three segments characterized by their distinct properties in relation to salinity, hydrology, ecosystems, etc. Historical records from 1997 to 2014 were then analysed using statistical modelling to develop candidate nutrient criteria for the *** stage of the analysis was undertaken in combination with the study of nutrient status records from the 1980s,which were used to establish a baseline reference condition. The recommended criteria values of dissolved inorganic nitrogen（DIN） in Segments Ⅰ, Ⅱ and Ⅲ of the Jiulong River Estuary are 64, 21 and 14 μmol/L,respectively, and the corresponding values for soluble reactive phosphorus（SRP） are 0.89, 0.76 and 0.89 μmol/L,respectively. It should be emphasised that these values are site-dependent, and that different results may be achieved at other locations depending on the physical and biogeochemical characteristics of an estuary, or even a single site within a catchment. It is hoped that by demonstrating a possible methodological approach and methods of nutrient criteria derivation in the Jiulong River Estuary, the current study will offer researchers some fundamental ba

关键词： estuarine segmentation nutrient criteria ecosystems based approach

Exploring plant adaptation strategies to phosphorus limitation induced by nitrogen addition:foliar phosphorus allocation and root functional traits analysis in two dominant subalpine tree species

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Journal of Plant Ecology 2024年第4期17卷 154-166页

作者： Yan Su Yongfeng Tang Yi Hu Meiyu Liu Xuyang Lu baoli Duan Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Sichuan Ecological Environment Construction Engineering Supervision Co. Ltd.Chengdu 610084China

Plants adapt to the limitation of soil phosphorus(P)induced by nitrogen(N)deposition through a complex interaction of various root and leaf functional *** this study,a pot experiment was conducted to explore the effects of different levels of N addition(control,low N[LN]:25 kg N ha^(-1) yr^(-1),high N[HN]:50 kg N ha^(-1) yr^(-1))on tree growth,leaf nutrient content,foliar P fractions and root characteristics of two dominant tree species,the pioneer species Salix rehderiana Schneid and the climax species Abies fabri(Mast.)Craib,in a subalpine forest in southwestern *** results demonstrated that LN addition had a minimal impact on leaf N and P ***,HN addition significantly decreased the leaf P content in both *** rehderiana exhibited more pronounced increases in specific root length and specific root area under P deficiency triggered by HN addition when compared with *** contrast,*** showed weaker morphological responses to N addition but had a higher proportion of foliar P to metabolic P,as well as higher root exudates rate and root phosphatase activity in response to HN *** fabri employs a synergistic approach by allocating a greater amount of leaf P to metabolite P and extracting P from the soil through P-mobilizing exudates and root phosphatase activity,while *** exhibits higher flexibility in modifying its root morphology in response to P limitation induced by HN *** study provides insights into subalpine tree species adaptation to N-induced P limitation,emphasizing its significance for guiding forest management and conservation in the context of global climate change.

关键词： N deposition root functional traits root morphology root exudation P-scavenging strategy