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Lactiplantibacillus plantarum FRT4 attenuates high-energy low-protein dietinduced fatty liver hemorrhage syndrome in laying hens through regulating gut-liver axis
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作者 Daojie Li Hongying Cai +5 位作者 guohua liu Yunsheng Han Kai Qiu Weiwei liu Kun Meng Peilong Yang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1292-1311,共20页
Background Fatty liver hemorrhage syndrome(FLHS)becomes one of the most major factors resulting in the laying hen death for caged egg production.This study aimed to investigate the therapeutic effects of Lactiplantiba... Background Fatty liver hemorrhage syndrome(FLHS)becomes one of the most major factors resulting in the laying hen death for caged egg production.This study aimed to investigate the therapeutic effects of Lactiplantibacillus plan-tarum(Lp.plantarum)FRT4 on FLHS model in laying hen with a focus on liver lipid metabolism,and gut microbiota.Results The FLHS model of laying hens was established by feeding a high-energy low-protein(HELP)diet,and the treatment groups were fed a HELP diet supplemented with differential proportions of Lp.plantarum FRT4.The results indicated that Lp.plantarum FRT4 increased laying rate,and reduced the liver lipid accumulation by regulating lipid metabolism(lipid synthesis and transport)and improving the gut microbiota composition.Moreover,Lp.plan-tarum FRT4 regulated the liver glycerophospholipid metabolism.Meanwhile,“gut-liver”axis analysis showed that there was a correlation between gut microbiota and lipid metabolites.Conclusions The results indicated that Lp.plantarum FRT4 improved the laying performance and alleviated FLHS in HELP diet-induced laying hens through regulating“gut-liver”axis.Our findings reveal that glycerophospholipid metabolism could be the underlying mechanism for the anti-FLHS effect of Lp.plantarum FRT4 and for future use of Lp.plantarum FRT4 as an excellent additive for the prevention and mitigation of FLHS in laying hens. 展开更多
关键词 Fatty liver hemorrhage syndrome Gut microbiota Lactiplantibacillus plantarum FRT4 Laying hens Lipid metabolism
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Auxiliary guidance manufacture and revealing potential mechanism of perovskite solar cell using machine learning
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作者 Quan Zhang Jianqi Wang guohua liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第11期146-157,I0004,共13页
To promote the development of global carbon neutrality,perovskite solar cells(PSCs)have become a research hotspot in related fields.How to obtain PSCs with expected performance and explore the potential factors affect... To promote the development of global carbon neutrality,perovskite solar cells(PSCs)have become a research hotspot in related fields.How to obtain PSCs with expected performance and explore the potential factors affecting device performance are the research priorities in related fields.Although some classical computational methods can facilitate material development,they typically require complex mathematical approximations and manual feature screening processes,which have certain subjectivity and one-sidedness,limiting the performance of the model.In order to alleviate the above challenges,this paper proposes a machine learning(ML)model based on neural networks.The model can assist both PSCs design and analysis of their potential mechanism,demonstrating enhanced and comprehensive auxiliary capabilities.To make the model have higher feasibility and fit the real experimental process more closely,this paper collects the corresponding real experimental data from numerous research papers to develop the model.Compared with other classical ML methods,the proposed model achieved better overall performance.Regarding analysis of underlying mechanism,the relevant laws explored by the model are consistent with the actual experiment results of existing articles.The model exhibits great potential to discover complex laws that are difficult for humans to discover directly.In addition,we also fabricated PSCs to verify the guidance ability of the model in this paper for real experiments.Eventually,the model achieved acceptable results.This work provides new insights into integrating ML methods and PSC design techniques,as well as bridging photovoltaic power generation technology and other fields. 展开更多
关键词 Machine learning Carbon neutrality PHOTOVOLTAIC Auxiliary experiment design
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企业间竞争对抗与竞争策略组合的动态演化——基于我国团购行业的案例研究 被引量:1
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作者 邓新明 郭雅楠 +2 位作者 刘国华 熊静怡 王惠子 《管理学季刊》 CSSCI 2018年第4期72-98,156,157,共29页
我国团购行业经历了商业史上最惨烈的行业周期演变,最后的市场胜利者“是如何‘活’下来的?”是一个值得深入探讨的问题。本文试图基于动态竞争理论,通过内容分析法,研究团购企业竞争过程中的竞争行动选择与互动策略,以及竞争策略组合... 我国团购行业经历了商业史上最惨烈的行业周期演变,最后的市场胜利者“是如何‘活’下来的?”是一个值得深入探讨的问题。本文试图基于动态竞争理论,通过内容分析法,研究团购企业竞争过程中的竞争行动选择与互动策略,以及竞争策略组合的整体特征和动态发展的规律,旨在找到团购企业在激烈的动态竞争环境下能够生存并发展起来的秘密“武器”。研究的主要结论如下:第一,在竞争行动层面,发现企业竞争行为的选择范围仍然只是局限于市场领域,主要实施的行动类型有造势、推出新产品、服务更新与升级、降价、合作与形象补救等。第二,在竞争互动层面,发现团购行业中大部分企业偏好对竞争者发起攻击,但响应程度不高;在具体的竞争攻防过程中,企业更偏好于采取战术性行动;同时企业偏好于大张旗鼓地向竞争对手发起攻击或响应。第三,在竞争策略组合层面,市场领导者偏好于实施适度多样化(即集中采取有限类型的竞争行动);同时倾向于采取具有较高变化性的竞争决策(即较低的竞争惯性)。第四,在竞争行动的动态演进层面,发现整个团购行业的优秀企业已经发展出了一种独特的竞争决策模式,即适度的竞争多样化与较高的竞争变化性组合实施,同时保持一定程度的行动创新性,这应该是现有团购企业能在惨烈的动态竞争中“活”下来的关键竞争原则。 展开更多
关键词 动态竞争 竞争策略组合 非市场行动 动态演进 团购行业
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Polyimide separators for rechargeable batteries 被引量:6
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作者 Ziheng Lu Fan Sui +7 位作者 Yue-E Miao guohua liu Cheng Li Wei Dong Jiang Cui Tianxi liu Junxiong Wu Chunlei Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第7期170-197,共28页
Separators are indispensable components of modern electrochemical energy storage devices such as lithium-ion batteries(LIBs).They perform the critical function of physically separating the electrodes to prevent short-... Separators are indispensable components of modern electrochemical energy storage devices such as lithium-ion batteries(LIBs).They perform the critical function of physically separating the electrodes to prevent short-circuits while permitting the ions to pass through.While conventional separators using polypropylene(PP) and polyethylene(PE) are prone to shrinkage and melting at relatively high temperatures(150℃ or above) causing short circuits and thermal runaway,separators made of thermally stable polyimides(PIs) are electrochemically stable and resistant to high temperatures,and possess good mechanical strength-making them a promising solution to the safety concerns of LIBs.In this review,the research progress on PI separators for use in LIBs is summarized with a special focus on molecular design and microstructural control.In view of the significant progress in advanced chemistries beyond LIBs,recent advances in PI-based membranes for applications in lithium-sulfur,lithium-metal,and solid-state batteries are also reviewed.Finally,practical issues are also discussed along with their prospects. 展开更多
关键词 POLYIMIDE Lithium-ion batteries SEPARATORS Solid-state batteries Molecular design
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Molecular mechanisms of growth depression in broiler chickens(Gallus Gallus domesticus)mediated by immune stress:a hepatic proteome study 被引量:5
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作者 Aijuan Zheng Anrong Zhang +5 位作者 Zhimin Chen Shoaib Ahmed Pirzado Wenhuan Chang Huiyi Cai Wayne L.Bryden guohua liu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第4期1498-1516,共19页
Background:Immunological stress decreases feed intake,suppresses growth and induces economic losses.However,the underlying molecular mechanism remains unclear.Label-free liquid chromatography and mass spectrometry(LC-... Background:Immunological stress decreases feed intake,suppresses growth and induces economic losses.However,the underlying molecular mechanism remains unclear.Label-free liquid chromatography and mass spectrometry(LC-MS)proteomics techniques were employed to investigate effects of immune stress on the hepatic proteome changes of Arbor Acres broilers(Gallus Gallus domesticus)challenged with Escherichia coli lipopolysaccharide(LPS).Results:Proteomic analysis indicated that 111 proteins were differentially expressed in the liver of broiler chickens from the immune stress group.Of these,28 proteins were down-regulated,and 83 proteins were up-regulated in the immune stress group.Enrichment analysis showed that immune stress upregulated the expression of hepatic proteins involved in defense function,amino acid catabolism,ion transport,wound healing,and hormone secretion.Furthermore,immune stress increased valine,leucine and isoleucine degradation pathways.Conclusion:The data suggests that growth depression of broiler chickens induced by immune stress is triggered by hepatic proteome alterations,and provides a new insight into the mechanism by which immune challenge impairs poultry production. 展开更多
关键词 Broiler chickens Hepatic proteome Immune stress LIPOPOLYSACCHARIDE
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A Weighted Threshold Secret Sharing Scheme for Remote Sensing Images Based on Chinese Remainder Theorem 被引量:4
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作者 Qi He Shui Yu +5 位作者 Huifang Xu Jia liu Dongmei Huang guohua liu Fangqin Xu Yanling Du 《Computers, Materials & Continua》 SCIE EI 2019年第2期349-361,共13页
The recent advances in remote sensing and computer techniques give birth to the explosive growth of remote sensing images.The emergence of cloud storage has brought new opportunities for storage and management of mass... The recent advances in remote sensing and computer techniques give birth to the explosive growth of remote sensing images.The emergence of cloud storage has brought new opportunities for storage and management of massive remote sensing images with its large storage space,cost savings.However,the openness of cloud brings challenges for image data security.In this paper,we propose a weighted image sharing scheme to ensure the security of remote sensing in cloud environment,which takes the weights of participants(i.e.,cloud service providers)into consideration.An extended Mignotte sequence is constructed according to the weights of participants,and we can generate image shadow shares based on the hash value which can be obtained from gray value of remote sensing images.Then we store the shadows in every cloud service provider,respectively.At last,we restore the remote sensing image based on the Chinese Remainder Theorem.Experimental results show the proposed scheme can effectively realize the secure storage of remote sensing images in the cloud.The experiment also shows that no matter weight values,each service providers only needs to save one share,which simplifies the management and usage,it also reduces the transmission of secret information,strengthens the security and practicality of this scheme. 展开更多
关键词 Remote sensing image security CLOUD STORAGE weighted threshold
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Variation in individual biomass decreases faster than mean biomass with increasing density of bamboo stands 被引量:2
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作者 guohua liu Cang Hui +4 位作者 Ming Chen Lauren SPile GGeoff Wang Fusheng Wang Peijian Shi 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第3期981-987,共7页
The total biomass of a stand is an indicator of stand productivity and is closely related to the density of plants. According to the self-thinning law, mean individual biomass follows a negative power law with plant d... The total biomass of a stand is an indicator of stand productivity and is closely related to the density of plants. According to the self-thinning law, mean individual biomass follows a negative power law with plant density. If the variance of individual biomass is constant, we can expect increased stand productivity with increasing plant density. However, Taylor's power law(TPL) that relates the variance and the mean of many biological measures(e.g. bilateral areal differences of a leaf, plant biomass atdifferent times, developmental rates at different temperatures, population densities on different spatial or temporal scales), affects the estimate of stand productivity when it is defined as the total biomass of large plants in a stand.Because the variance of individual biomass decreases faster than mean individual biomass, differences in individual biomass decline with increasing density, leading to more homogeneous timbers of greater economic value. We tested whether TPL in plant biomass holds for different species and whether the variance of individual biomass changes faster than the mean with increasing stand density.The height, ground diameter and fresh weight of 50 bamboo species were measured in 50 stands ranging from 1 m by 1 m to 30 m by 30 m to ensure more than 150 bamboos in every stand. We separately examined TPL in height,ground diameter, and weight, and found that TPL holds for all three biological measures, with the relationship strongest for weight. Using analysis of covariance to compare the regression slopes of logarithmic mean and variance against the logarithm of density, we found that the variance in individual biomass declined faster than the mean with increasing density. This suggests that dense planting reduced mean individual biomass but homogenized individual biomass. Thus, there exists a trade-off between effective stand productivity and stand density for optimal forest management. Sparse planting leads to large variation in individual biomass, whereas dense planting reduces mean individual biomass. Consequently, stand density for a plantation should be set based on this trade-off with reference to market demands. 展开更多
关键词 BAMBOO Linear fitting SELF-THINNING LAW Taylor's power LAW Variance
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Shoot proliferation and callus regeneration from nodular buds of Drepanostachyum luodianense 被引量:1
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作者 Shuyan Lin guohua liu +3 位作者 Tingting Guo Li Zhang Shuguang Wang Yulong Ding 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期1997-2005,共9页
This research reports on an efficient shoot proliferation and callus regeneration system for bamboo.Young, semi-lignified branches with one lateral bud from Drepanostachyum luodianense(Yi et R. S. Wang) Keng f.were us... This research reports on an efficient shoot proliferation and callus regeneration system for bamboo.Young, semi-lignified branches with one lateral bud from Drepanostachyum luodianense(Yi et R. S. Wang) Keng f.were used as explants. Disinfection with 0.1% HgCl2 for 8 min was the optimum treatment and the best medium for bud initiation was Murashige and Skoog(MS) medium containing 3.0 mg L-16-benzyladenine(BA). Multiple shoots were induced from nodal shoot segments on MS medium containing 5.0 mg L-1 BA, 0.5 mg L-1 kinetin(Kin), and 1.0 mg L-1 naphthaleneacetic acid(NAA). The highest frequency of callus formation(65.6%) was on MS medium containing 4.0 mg L-12,4-dichlorophenoxyacetic acid(2, 4-D), 0.5 mg L-1 NAA, and 0.1 mg L-1 thidiazuron(TDZ). The optimum medium for callus proliferation was MS medium with 4 mg L-12,4-D, 0.5 mg L-1 TDZ and 0.5 mg L-1 NAA, and the optimum hormone combination was 4 mg L-1 BA ? 0.5 mg L-1 NAA for callus redifferentiation(up to 85.6%). A 100% rooting was achieved on MS medium supplemented with 2.0 mg L-1 NAA and 0.5 mg L-13-indole butyric acid(IBA). Rooted plantlets were acclimatized in a greenhouse in humus soil ? perlite(1:1) substrate. These micropropagated callus induction and regeneration systems for bamboo will be useful for genetic engineering and multiplication. 展开更多
关键词 MICROPROPAGATION BAMBOO SHOOT proliferation CALLUS regeneration Transplantation
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Review of regional carbon counting methods for the Chinese major ecological engineering programs 被引量:3
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作者 Ji Zheng Xiaohua Wei +3 位作者 Yuanqiu liu guohua liu Weifeng Wang Wenfei liu 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第4期727-738,共12页
In order to improve environment and relieve poverty, China has launched a series of major ecological engineering programs since the 1980 s. These include the Natural Forest Conservation Program, the Sloping Cropland C... In order to improve environment and relieve poverty, China has launched a series of major ecological engineering programs since the 1980 s. These include the Natural Forest Conservation Program, the Sloping Cropland Conversion Program, the Desertification Combating Program, and the Protection Forest System Construction Program. There is a growing need to quantify the contributions of these programs to regional carbon stocks.However, the lack of widely accepted, robust methods is one of the key obstacles to quantification. The objective of this study was to review existing methods for quantifying regional carbon stocks and then recommend suitable ones for the Chinese ecological engineering programs. We expect that the recommended methods can be applied to elsewhere in the world where there are similar characteristics and objectives. 展开更多
关键词 programs elsewhere vegetation contributions stocks Conversion forests obstacles biomass expect
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A TMA-Seq2seq Network for Multi-Factor Time Series Sea Surface Temperature Prediction
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作者 Qi He Wenlong Li +6 位作者 Zengzhou Hao guohua liu Dongmei Huang Wei Song Huifang Xu Fayez Alqahtani Jeong-Uk Kim 《Computers, Materials & Continua》 SCIE EI 2022年第10期51-67,共17页
Sea surface temperature (SST) is closely related to global climatechange, ocean ecosystem, and ocean disaster. Accurate prediction of SST isan urgent and challenging task. With a vast amount of ocean monitoring dataar... Sea surface temperature (SST) is closely related to global climatechange, ocean ecosystem, and ocean disaster. Accurate prediction of SST isan urgent and challenging task. With a vast amount of ocean monitoring dataare continually collected, data-driven methods for SST time-series predictionshow promising results. However, they are limited by neglecting complexinteractions between SST and other ocean environmental factors, such as airtemperature and wind speed. This paper uses multi-factor time series SSTdata to propose a sequence-to-sequence network with two-module attention(TMA-Seq2seq) for long-term time series SST prediction. Specifically, TMASeq2seq is an LSTM-based encoder-decoder architecture facilitated by factorand temporal-attention modules and the input of multi-factor time series. Ittakes six-factor time series as the input, namely air temperature, air pressure,wind speed, wind direction, SST, and SST anomaly (SSTA). A factor attentionmodule is first designed to adaptively learn the effect of different factors onSST, followed by an encoder to extract factor-attention weighted features asfeature representations. And then, a temporal attention module is designedto adaptively select the hidden states of the encoder across all time steps tolearn more robust temporal relationships. The decoder follows the temporalattention module to decode the feature vector concatenated from the weightedfeatures and original input feature. Finally, we use a fully-connect layer tomap the feature into prediction results. With the two attention modules, ourmodel effectively improves the prediction accuracy of SST since it can notonly extract relevant factor features but also boost the long-term dependency.Extensive experiments on the datasets of China Coastal Sites (CCS) demonstrate that our proposed model outperforms other methods, reaching 98.29%in prediction accuracy (PACC) and 0.34 in root mean square error (RMSE).Moreover, SST prediction experiments in China’s East, South, and Yellow Seasite data show that the proposed model has strong robustness and multi-siteapplicability. 展开更多
关键词 Sea surface temperature multi-factor ATTENTION long short-term memory
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Ribbon Element on Co-Frobenius Quasitriangular Hopf Algebras
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作者 guohua liu 《Applied Mathematics》 2010年第3期230-233,共4页
Let (H, R) be a co-Frobenius quasitriangular Hopf algebra with antipode S. Denote the set of group-like elements in H by G (H). In this paper, we find a necessary and sufficient condition for (H, R) to have a ribbon e... Let (H, R) be a co-Frobenius quasitriangular Hopf algebra with antipode S. Denote the set of group-like elements in H by G (H). In this paper, we find a necessary and sufficient condition for (H, R) to have a ribbon element. The condition gives a connection with the order of G (H) and the order of S2. 展开更多
关键词 Co-Frobenius HOPF ALGEBRA RIBBON ELEMENT
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A Well-Balanced Numerical Model for the Simulation of Long Waves over Complex Domains
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作者 Gangfeng Wu Zhiguo He guohua liu 《Journal of Applied Mathematics and Physics》 2014年第6期418-424,共7页
This paper presents a well-balanced two-dimensional (2D) finite volume model to simulate the propagation, runup and rundown of long wave. Non-staggered grid is adopted to discretize the governing equation and the inte... This paper presents a well-balanced two-dimensional (2D) finite volume model to simulate the propagation, runup and rundown of long wave. Non-staggered grid is adopted to discretize the governing equation and the intercell flux is computed using a central upwind scheme, which is a Riemann-problem-solver-free method for hyperbolic conservation laws. The nonnegative reconstruction method for water depth is implemented in the present model to treat the appearance of wet/dry fronts, and the friction term is solved by a semi-implicit scheme to ensure the stability of the model. The Euler method is applied to update flow variable to the new time level. The model is verified against two experimental cases and good agreements are observed between numerical results and observed data. 展开更多
关键词 Long Wave Central UPWIND Scheme Well-Balanced WETTING and Drying
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Study on the Concentration Inversion of NO &NO2 Gas from the Vehicle Exhaust Based on Weighted PLS
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作者 Kai Zhang Yujun Zhang +7 位作者 Kun You Yibing Lu Qixing Tang Ying He guohua liu Boqiang Fan Dongqi Yu Wenqing liu 《Optics and Photonics Journal》 2017年第8期106-115,共10页
It becomes a key technology to measure the concentration of the vehicle exhaust components with the absorption spectra. But because of the overlap of gas absorption bands, how to separate the absorption information of... It becomes a key technology to measure the concentration of the vehicle exhaust components with the absorption spectra. But because of the overlap of gas absorption bands, how to separate the absorption information of each component gas from the mixed absorption spectra has become the key point to restrict the precision of the optical detection method. In this paper, the ex-perimental platform for the absorption spectrum of vehicle exhaust components has been established. Based on the ultraviolet absorption spectra measured with the platform of exhaust gas NO & NO2, the concentration regression model for the two components has been established with weighted partial least squares regression (WPLS). Finally the each spectral characteristic information of NO & NO2 gas has been separated and the concentration of each corresponding component has been reversed successfully. 展开更多
关键词 Absorption Spectra NO & NO2 GAS WEIGHTED Partial Least SQUARES Regression Concentration INVERSION
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Study on Ethical Issues and Countermeasures of Human Resources Management in Corporation
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作者 guohua liu 《International Journal of Technology Management》 2014年第9期39-41,共3页
With the rapid development of civilization and economy, society and company are attaching greater importance to the management of human resource, and it has draw manager's attention on how to manage human resource ef... With the rapid development of civilization and economy, society and company are attaching greater importance to the management of human resource, and it has draw manager's attention on how to manage human resource effectively. Therefore, the paper put forward the corresponding countermeasures by analyzing problems in human resource management. 展开更多
关键词 CORPORATION human resource management PROBLEM SOLUTION
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Optical edge-to-screw singularity state conversions
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作者 HAOLIN LIN JUNHUI JIA +4 位作者 guohua liu YANWEN HU ZHEN LI ZHENQIANG CHEN SHENHE FU 《Photonics Research》 SCIE EI CAS CSCD 2024年第8期1689-1695,共7页
Optical singularity states,which significantly affect propagation properties of light in free space or optical medium,can be geometrically classified into screw and edge types.These different types of singularity stat... Optical singularity states,which significantly affect propagation properties of light in free space or optical medium,can be geometrically classified into screw and edge types.These different types of singularity states do not exhibit direct connection,being decoupled from each other in the absence of external perturbations.Here we demonstrate a novel optical process in which a higher-order edge singularity state initially nested in the propagating Gaussian light field gradually involves into a screw singularity with a new-born topological charge determined by order of the edge state.The considered edge state comprises an equal superposition of oppositely charged vortex and antivortex modes.We theoretically and experimentally realize this edge-to-screw conversion process by introducing intrinsic vortex–antivortex interaction.We also present a geometrical representation for mapping this dynamical process,based on the higher-order orbital Poincarésphere.Within this framework,the edge-to-screw conversion is explained by a mapping of state evolution from the equator to the north or south pole of the Poincarésphere.Our demonstration provides a novel approach for manipulating singularity state by the intrinsic vortex–antivortex interactions.The presented phenomenon can be also generalized to other wave systems such as matter wave,water wave,and acoustic wave. 展开更多
关键词 INTERACTION POINCARÉ WAVE
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PDLLA length on anti-breast cancer efficacy of acid-responsive self-assembling mPEG-PDLLA–docetaxel conjugates
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作者 Tao liu Hui Zou +7 位作者 Jingqing Mu Xi Zhang guohua liu Na Yu Bo Yuan Xiaoyong Yuan Xingjie Liang Shutao Guo 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第9期225-229,共5页
Engineering small-molecule drugs into nanoparticulate formulations provides an unprecedented opportunity to improve the performance of traditional chemo drugs,but suffers from poor compatibility between drugs and nano... Engineering small-molecule drugs into nanoparticulate formulations provides an unprecedented opportunity to improve the performance of traditional chemo drugs,but suffers from poor compatibility between drugs and nanocarriers.Stimuli-responsive mPEG-PDLLA–drug conjugate-based nanomedicines can facilitate the exploitation of beneficial properties of the carrier and enable the practical fabrication of highly efficacious self-assembled nanomedicines.However,the influence of hydrophobic length on the performance of this type of nanomedicine is little known.Here we synthesized two acid-sensitive ketal-linked mPEG-PDLLA–docetaxel prodrugs with different lengths of PDLLA,and engineered them into self-assembled sub-20 nm micellar nanomedicines for breast cancer chemotherapy.We found that the nanomedicine consisting of a mPEG-PDLLA–docetaxel prodrug with the shorter length of PDLLA stood out due to its potent cytotoxicity,deep penetration into multicellular spheroids,and improved in vivo anticancer performance.Additionally,our prodrug-based nanomedicines outperformed the generic formulation of commercial Nanoxel in terms of safety profile,tolerated doses,and tumor suppression.Our findings indicate that the hydrophobic content of a polymeric prodrug nanomedicine plays an important role in the performance of the nanomedicine,and should be instructive for developing polymeric prodrug-based nanomedicines with clinical translational potential. 展开更多
关键词 NANOMEDICINE PRODRUG DOCETAXEL mPEG-PDLLA Acid-sensitive
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具有优越电催化析氢性能的超小碳负载FeRu合金
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作者 刘国华 张照艳 +6 位作者 刘文宁 杨文昕 安丽 曲丹 刘弈畅 汪夏燕 孙再成 《Science China Materials》 SCIE EI CAS CSCD 2023年第7期2672-2679,共8页
电化学水分解是将可再生能源产生的间歇性电能转化为高纯度氢气的一种极具前景的绿色能源技术.目前,高效制氢催化剂主要由贵金属及其化合物组成,而贵金属的高成本及稀缺性,限制了其在大规模工业化制氢中的应用.因此,探索低成本,高电化... 电化学水分解是将可再生能源产生的间歇性电能转化为高纯度氢气的一种极具前景的绿色能源技术.目前,高效制氢催化剂主要由贵金属及其化合物组成,而贵金属的高成本及稀缺性,限制了其在大规模工业化制氢中的应用.因此,探索低成本,高电化学活性、高稳定性的电解水制氢催化剂至关重要.合金化材料以短程或长程有序结构存在,具有增强的电化学性能.因此,本文采用两步法制备超小碳负载FeRu合金纳米电催化剂并将其应用于电催化析氢反应.Fe_(0.05)Ru_(0.05)/XC-72双功能电催化剂粒径为2.1 nm,在碱性淡水和海水电解质中表现出优异的活性和耐久性.10 mA cm^(-2)时,在1 mol L^(-1)KOH、1 mol L^(-1)KOH+0.5 mol L^(-1)NaCl和1 mol L^(-1)KOH+海水中分别表现出13、15和18 mV的过电位.在1 mol L^(-1)KOH介质和-0.07 V(相比于可逆氢电极)条件下,Fe_(0.05)Ru_(0.05)/XC-72的析氢质量活性高达11.32Amg^(-1)_(noble metal).在1 mol L^(-1)KOH中,Fe_(0.05)Ru_(0.05)/XC-72电催化剂具有24 h以上的长期析氢反应(HER)稳定性.理论计算表明,引入Fe形成的FeRu合金可以诱导电子效应,使其对*H的吸附能力增强,进一步提高了HER性能.本工作对制备高电活性、高稳定性的钌基电催化剂具有重要的启发意义. 展开更多
关键词 FeRu alloy ELECTROCATALYST hydrogen evolution reaction electronic effect
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Higher-order optical rabi oscillations
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作者 guohua liu Shenhe Fu +3 位作者 Siqi Zhu Hao Yin Zhen Li Zhenqiang Chen 《Fundamental Research》 CSCD 2023年第6期898-903,共6页
Rabi oscillations express a phenomenon of periodic conversion between two wave states in a coupled system.The finding of Rabi oscillation has led to important applications in many different disciplines.Despite great p... Rabi oscillations express a phenomenon of periodic conversion between two wave states in a coupled system.The finding of Rabi oscillation has led to important applications in many different disciplines.Despite great progress,it is still unknown whether the Rabi oscillating state can be excited in the framework of the higher-order vector vortex regime.Here,we demonstrate in theory that the higher-order vector vortex light beams can be Rabi oscillating during evolution in an optical coupling system.This new classical oscillating state of light is characterized by a topologically shaped wavefront and coupled with spatially varying polarization.The vector vortex state exhibits a harmonic oscillatory property in the resonant and nonresonant conditions but differs greatly in Rabi oscillating frequencies.During Rabi oscillation,the complex state maintains its topology and intensity profile,while its intrinsic polarization pattern varies adiabatically in a periodic manner.We present an interpretation of the Rabi oscillation of the higher-order wave states in terms of the coupled-mode theory.Furthermore,we reveal a symmetry-protected transition between two Rabi oscillating modes,driven by a slowly varying phase mismatch.This Rabi transition has not been reported in either quantum mechanics or any other physical setting.This work advances the research of Rabi oscillation into the higher-order regime,and it may lead to novel applications in classical and quantum optics. 展开更多
关键词 Rabi oscillations Vector vortex light fields Higher-order beams Polarization control Coupled mode system
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Spin-orbit Rabi oscillations in optically synthesized magnetic fields
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作者 guohua liu Xiliang Zhang +4 位作者 Xin Zhang Yanwen Hu Zhen Li Zhenqiang Chen Shenhe Fu 《Light(Science & Applications)》 SCIE EI CSCD 2023年第9期1930-1942,共13页
Rabi oscillation has been proven to be one of the cornerstones of quantum mechanics,triggering substantial investigations in different disciplines and various important applications both in the classical and quantum r... Rabi oscillation has been proven to be one of the cornerstones of quantum mechanics,triggering substantial investigations in different disciplines and various important applications both in the classical and quantum regimes.So far,two independent classes of wave states in the Rabi oscillations have been revealed as spin waves and orbital waves,while a Rabi wave state simultaneously merging the spin and orbital angular momentum has remained elusive.Here we report on the experimental and theoretical observation and control of spin–orbit-coupled Rabi oscillations in the higher-order regime of light.We constitute a pseudo spin-1/2 formalism and optically synthesize a magnetization vector through light-crystal interaction.We observe simultaneous oscillations of these ingredients in weak and strong coupling regimes,which are effectively controlled by a beam-dependent synthetic magnetic field.We introduce an electrically tunable platform,allowing fine control of transition between different oscillatory modes,resulting in an emission of orbital-angular-momentum beams with tunable topological structures.Our results constitute a general framework to explore spin–orbit couplings in the higher-order regime,offering routes to manipulating the spin and orbital angular momentum in three and four dimensions.The close analogy with the Pauli equation in quantum mechanics,nonlinear optics,etc.,implies that the demonstrated concept can be readily generalized to different disciplines. 展开更多
关键词 FIELD ORBITAL MOMENTUM
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退化高寒草地的近自然恢复:理论基础与技术途径 被引量:57
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作者 贺金生 卜海燕 +6 位作者 胡小文 冯彦皓 李守丽 朱剑霄 刘国华 王彦荣 南志标 《科学通报》 EI CAS CSCD 北大核心 2020年第34期3898-3908,共11页
近几十年来,青藏高原高寒草地植被活动整体上趋于向好,但大部分草地仍然存在不同程度的退化,局部有恶化的态势.在青藏高原生态屏障保护与建设过程中,由于建植或改良的草地草种单一、优良乡土草种少,加之受高寒气候的限制,群落稳定性和... 近几十年来,青藏高原高寒草地植被活动整体上趋于向好,但大部分草地仍然存在不同程度的退化,局部有恶化的态势.在青藏高原生态屏障保护与建设过程中,由于建植或改良的草地草种单一、优良乡土草种少,加之受高寒气候的限制,群落稳定性和可持续性不强,使得生态系统多功能性和多服务性往往难以完全恢复.因此,探索行之有效的可持续恢复模式迫在眉睫.本文提出了对青藏高原高寒草地实施近自然恢复(close-to-nature restoration)的理念,从生物多样性、生态系统多功能性和多服务性、生态系统稳定性的理论出发,结合青藏高原高寒生态系统的特点,论述了近自然恢复是退化高寒草地生态恢复的必然选择.据此,本文提出优良乡土草种扩繁、组配及其补播技术是高寒草地近自然恢复技术亟须解决的瓶颈,土壤养分及微生物调控相结合是“近自然恢复”技术的重要辅助措施.该理论与技术途径为青藏高原退化高寒草地生态系统恢复提供了一个基于自然的解决方案. 展开更多
关键词 近自然恢复 高寒草地 生物多样性 生态系统多功能性 生态系统多服务性 乡土草种
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