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| 1 | Chronic Nitrogen Fertilization Modulates Competitive Interactions Among Microbial Ammonia Oxidizers in a Loess Soil显示文摘Nitrogen(N) application may lead to niche segregation of soil ammonia-oxidizing archaea(AOA) and bacteria(AOB), thereby reducing the competitive interactions between AOA and AOB due to higher ammonium substrate availability. However, the adaptive mechanisms of AOA and AOB under N enrichment remain poorly understood. Stable isotope probing(SIP) microcosm incubation was employed to reveal community changes of active AOA and AOB in a loess soil from a field experiment growing potatoes that received no N(control, CK), low N(LN, 75 kg N ha^(-1)), and high N(HN, 375 kg N ha^(-1)). The results showed that the soil potential nitrification rate(PNR) was measured by culturing of the soil samples from the field experiment. Soil PNR was significantly increased in HN by87.5% and 67.5% compared with CK and LN, respectively. Compared with CK, the^(13)C-amoA genes of soil AOA and AOB in HN had 2.58 × 10~4 and 1.55 × 10~6 copies, representing 1.6-and 16.2-fold increase respectively. It was indicated that AOB dominated soil ammonia oxidation. A phylogenetic analysis of the^(13)C-amoA gene showed that N application significantly increased the proportion of54 d9-like AOA up to 90% in HN, while the Nitrososphaera gargensis-like and Nitrososphaera viennensis-like AOA were inhibited and completely disappeared. Nitrogen application also resulted in the community shift of active AOB-dominant group from Nitrosospira briensis-like to Nitrosospira sp. TCH711-like. Our study provides compelling evidence for the emergence and maintenance of active nitrifying communities under the intensified N input to an agricultural ecosystem. | DONG Xingchen ZHANG Jian QIU Huizhen ZHANG He LUO Chaoyue DENG Delei SHEN Qirong JIA Zhongjun | 2019 | Pedosphere2019，29，1： | 0 |
| 2 | Feature Extraction of Chinese Characters Based on ASM Algorithm显示文摘In Chinese Calligraphy education,the computer-based evaluation on Chinese handwriting is one of the problems in the field of computer intelligent education.In this study,the method of feature comparison is first proposed in the process of computer-based evaluation on Chinese handwriting,focusing on automatically and accurately extracting the features of Chinese characters.Then,the key technologies applied in feature extraction of Chinese character were analyzed.It discussed the representation of features,aligns training samples,and reduces dimensions by principal component analysis,established local grayscale model,and converged the gray-scale information of target feature points through statistical analysis.The experimental results show that the accuracy of the algorithm is 93.84%. | Xingchen Wei Minhua Wu Liming Luo | 2020 | 国际计算机前沿大会会议论文集2020，，2： | 0 |
| 3 | Field and laboratory experimental studies on hard-rock tunnel excavation based on disc cutter coupled with high-pressure waterjet显示文摘The tunnel boring machine(TBM)is typically used in hard-rock tunnel excavation.Owing to the unsatisfactory adaptability of TBM to the surrounding rock,when crossing high-strength and high-wear strata,the TBM can easily cause defects,such as abnormal wear on cutters and overload damage to bearings,thus affecting the construction efficiency and cost.Therefore,high-pressure waterjet technology should be applied to assist in rock breaking for efficient TBM tunneling.In this study,the effects of water pressure,nozzle diameter,and nozzle speed on cutting are investigated via laboratory experiments of cutting hard rock using high-pressure waterjets.The penetration performance of the TBM under different water pressures is investigated via a field industrial penetration test.The results show that high-pressure waterjets are highly efficient for rock breaking and are suitable for industrial applications,as they can accommodate the advancing speed of the TBM and achieve high-efficiency rock breaking.However,during the operation of high-pressure waterjets,the ambient temperature and waterjet temperature in the tunnel increase significantly,which weakens the cooling effect of the cutterhead and decreases the construction efficiency of the TBM.Therefore,temperature control and cooling measures for high-pressure waterjets during their long-term operation must be identified.This study provides a useful reference for the design and construction of high-pressure water-jet-assisted cutterheads for breaking road headers. | He FEI Yiqiang LU Jinliang ZHANG Xingchen LUO Yimin XIA | 2023 | Frontiers of Structural and Civil Engineering2023，17，9： | 0 |
| 4 | Oral PLGA-based DNA vaccines using interferons as adjuvants remarkably promote the immune protection of grass carp(Ctenopharyngodon idella)against GCRV infection显示文摘Grass carp hemorrhagic disease caused by grass carp reovirus(GCRV)results in significant economic losses to the global grass carp aquaculture industry.Oral vaccination is an ideal choice for disease precaution in aquaculture.However,oral vaccine can be degraded in the gut.Therefore,the selection of loading materials is essential.In this study,the S6 and S7 fragments(encoding the outer capsid protein VP4 and fibronectin VP56 of GCRV)and grass carp interferons(IFNs),including IFN1,IFN3,and IFNγ2 were used to create DNA vaccines and adjuvants based on pcDNA3.1,respectively.The oral DNA vaccine was encapsulated in poly(lactic-co-glycolic acid)(PLGA)and polyvinyl alcohol(PVA)with IFNs.The PLGA-PVA(PP)nano-microspheres were prepared by double emulsionsolvent evaporation technique.Using transmission electron microscopy and dynamic light scattering assays,it was determined the vaccines had a spherical structure with uniform particle size(643.5±35.3 nm).The nanomicrospheres possessed excellent encapsulation efficiency(81.6±2.6%)and loading rate(0.54±0.02%),and simultaneously exhibited negligible hemolytic activity and cell toxicity.The protection rate and tissue viral loads post-GCRV challenge in grass carp were assessed.The oral PP nano-microsphere with pVP4 t pIFN1(PP41)vaccine increased protection rate by 44%compared with the control group and was correlated with relatively low viral loads in the spleen,head kidney,and hindgut.Further,three crucial serum biochemical indexes,total superoxide dismutase(TSOD),complement C3(C3),and lysozyme(LZM),were also dramatically increased.Furthermore,mRNA expressions of representative immune-related genes(IgM,IFN1,IFNγ2,MHC-I,and CD8α)in the head kidney and spleen were significantly enhanced.In addition,mRNA expression of IgT was significantly boosted in the hindgut.The results indicate that DNA vaccine capsulated with PP is effective against GCRV infection.The present study provides insights into a prospective strategy for oral vaccine development in aquaculture. | Chaolin Jiang Xingchen Huo Lingjie Tang Meidi Hu Chunrong Yang Daji Luo Jianguo Su | 2023 | Water Biology and Security2023，2，2： | 0 |
| 5 | Tailoring the multiscale mechanics of tunable decellularized extracellular matrix (dECM) for wound healing through immunomodulation显示文摘With the discovery of the pivotal role of macrophages in tissue regeneration through shaping the tissue immune microenvironment, various immunomodulatory strategies have been proposed to modify traditional biomaterials. Decellularized extracellular matrix (dECM) has been extensively used in the clinical treatment of tissue injury due to its favorable biocompatibility and similarity to the native tissue environment. However, most reported decellularization protocols may cause damage to the native structure of dECM, which undermines its inherent advantages and potential clinical applications. Here, we introduce a mechanically tunable dECM prepared by optimizing the freeze-thaw cycles. We demonstrated that the alteration in micromechanical properties of dECM resulting from the cyclic freeze-thaw process contributes to distinct macrophage-mediated host immune responses to the materials, which are recently recognized to play a pivotal role in determining the outcome of tissue regeneration. Our sequencing data further revealed that the immunomodulatory effect of dECM was induced via the mechnotrasduction pathways in macrophages. Next, we tested the dECM in a rat skin injury model and found an enhanced micromechanical property of dECM achieved with three freeze-thaw cycles significantly promoted the M2 polarization of macrophages, leading to superior wound healing. These findings suggest that the immunomodulatory property of dECM can be efficiently manipulated by tailoring its inherent micromechanical properties during the decellularization process. Therefore, our mechanics-immunomodulation-based strategy provides new insights into the development of advanced biomaterials for wound healing. | Pu Luo Ruoxuan Huang You Wu Xingchen Liu Zhengjie Shan Li Gong Shudan Deng Haiwen Liu Jinghan Fang Shiyu Wu Xiayi Wu Quan Liu Zetao Chen Kelvin W.K.Yeung Wei Qiao Shoucheng Chen Zhuofan Chen | 2023 | Bioactive Materials2023，，10： | 0 |
| 6 | Photometric Redshift Estimates using Bayesian Neural Networks in the CSST Survey显示文摘Galaxy photometric redshift(photoz)is crucial in cosmological studies,such as weak gravitational lensing and galaxy angular clustering measurements.In this work,we try to extract photoz information and construct its probability distribution function(PDF)using the Bayesian neural networks from both galaxy flux and image data expected to be obtained by the China Space Station Telescope(CSST).The mock galaxy images are generated from the Hubble Space Telescope-Advanced Camera for Surveys(HST-ACS)and COSMOS catalogs,in which the CSST instrumental effects are carefully considered.In addition,the galaxy flux data are measured from galaxy images using aperture photometry.We construct a Bayesian multilayer perceptron(B-MLP)and Bayesian convolutional neural network(B-CNN)to predict photoz along with the PDFs from fluxes and images,respectively.We combine the B-MLP and B-CNN together,and construct a hybrid network and employ the transfer learning techniques to investigate the improvement of including both flux and image data.For galaxy samples with signal-to-noise ratio(SNR)>10 in g or i band,we find the accuracy and outlier fraction of photoz can achieve σ_(NMAD)=0.022 and η=2.35% for the B-MLP using flux data only,and σ_(NMAD)=0.022 and η=1.32% for the B-CNN using image data only.The Bayesian hybrid network can achieve σ_(NMAD)=0.021 and η=1.23%,and utilizing transfer learning technique can improve results to σ_(NMAD)=0.019 and η=1.17%,which can provide the most confident predictions with the lowest average uncertainty. | Xingchen Zhou Yan Gong Xian-Min Meng Xuelei Chen Zhu Chen Wei Du Liping Fu Zhijian Luo | 2022 | Research in Astronomy and Astrophysics2022，22，11： | 0 |
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