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| 1 | Comparison on Soil Carbon Stocks Between Urban and Suburban Topsoil in Beijing, China显示文摘The urban population and urbanized land in China have both increased markedly since the 1980 s. Urban and suburban developments have grown at unprecedented rates with unknown consequences for ecosystem functions. In particular, the effect of rapid urbanization on the storage of soil carbon has not been studied extensively. In this study, we compared the soil carbon stocks of different land use types in Beijing Municipality. We collected 490 top-soil samples(top 20 cm) from urban and suburban sites within the Sixth Ring Road of Beijing, which cover approximately 2400 km2, and the densities of soil organic carbon(SOC), soil inorganic carbon(SIC), and total carbon(TC) were analyzed to determine the spatial distribution of urban and suburban soil carbon characteristics across seven land use types. The results revealed significant differences in soil carbon densities among land use types. Additionally, urban soil had significantly higher SOC and SIC densities than suburban soil did, and suburban shelterbelts and productive plantations had lower SIC densities than the other land use types. The comparison of coefficients of variance(CVs) showed that carbon content of urban topsoil had a lower variability than that of suburban topsoil. Further findings revealed that soil carbon storage increased with built-up age. Urban soil built up for more than 20 years had higher densities of SOC, SIC and TC than both urban soil with less than 10 years and suburban soil. Correlation analyses indicated the existence of a significantly negative correlation between the SOC, SIC, and TC densities of urban soil and the distance to the urban core, and the distance variable alone explained 23.3% of the variation of SIC density and 13.8% of the variation of TC density. These results indicate that SOC and SIC accumulate in the urban topsoil under green space as a result of the conversion of agricultural land to urban land due to the urbanization in Beijing. | LUO Shanghua MAO Qizheng MA Keming | 2014 | Chinese Geographical Science2014，24，5： | 8 |
| 2 | Corneal Topograph-guided Laser Subepithelial Keratomileusis (LASEK)Corrects Decentered Ablation after Laser in Situ Keratomileusis (LASIK):A Case Report显示文摘Purpose:Corneal topograph-guided laser subepithelial keratomileusis (LASEK) can effectively correct decentered ablation occurring post laser in situ keratomileusis (LASIK) and to enhance our understanding and diagnosis of decentered ablation following LASIK. Methods:Previous studies in the relevant literature are reviewed, and a case report is provided. Results:A patient with high myopia undergoing LASIK in both eyes presented with distorted vision in the left eye, which interfered with the vision in the right eye and caused blurred vision in both eyes. The patient was unable to see objects with both eyes. After receiving corneal topography-guided LASEK,the signs of distorted vision in the left eye and bilateral blurred vision were significantly alleviated,and the patient could see objects with both eyes simultaneously. Conclusion: Clinical ophthalmologists should be aware of the occurrence of decentered ablation after LASIK. Corneal topography-guided LASEK is an efficacious tool for correcting decentered ablation. | Jing Zhang Huihui Luo Keming Yu | 2012 | Eye Science2012，27，4： | 2 |
| 3 | Excision of selectable marker gene from transgenic tobacco using the GM-gene-deletor system regulated by a heat-inducible promoter显示文摘 | Keming Luo Min Sun Wei Deng Shan Xu | 2008 | Biotechnology Letters2008，，7： | 2 |
| 4 | Spatial heterogeneity of urban soils:the case of the Beijing metropolitan region,China显示文摘Introduction:Urban soils are large pools of carbon,nitrogen,and other elements,supporting plant growth,sustaining biogeochemical cycles,and serving as the foundation for maintaining ecosystem function and services of urban green spaces(UGS).Quantifying urban soil properties is essential for assessing urban ecosystem services and detecting pollution.Characterizing spatial heterogeneity of urban soil properties,which may change with land use or urbanization,is crucial for understanding urban ecosystem functions.Methods:We collected 466 soil composite samples across the Beijing metropolitan region and then analyzed the heterogeneity of soil properties in UGS of Beijing metropolitan region by ANOVA along the urbanization gradient spanning different land uses.Results:Our results show that soil properties vary considerably among land-use types and along the urban-rural gradient.Soil moisture content,soil organic carbon(SOC),available phosphorus,available potassium,total nitrogen(TN),the ratio of SOC:TN(C/N),Pb,and Cu increased notably from suburbs to the urban core,while soil pH,bulk density,TN,Cr,Ni,and Mn were not significantly different across urbanization levels.Most soil properties,except soil TN,Cu,Cr,Ni,exhibited significant differences between different land uses.The highest levels of soil nutrients and heavy metals were found in roadsides and residential areas among all the land uses.Conclusions:The spatial heterogeneity of urban soils in the Beijing metropolitan region is mainly attributable to the different land uses.Soil nutrient content has increased in UGS due to fertilization and pollution.Contamination of urban soils by heavy metals is due largely to traffic emissions and pollution by industrial and household wastes.Although human activities tend to augment urban soil nutrient pools to maximize certain ecosystem services,they may inadvertently compromise these and other services by increasing pollution.Knowledge of urban soil spatial heterogeneity in UGS is indispensable for improving urban ecosystem management. | Qizheng Mao Ganlin Huang Alexander Buyantuev Jianguo Wu Shanghua Luo Keming Ma | 2014 | Ecological Processes2014，3，1： | 2 |
| 5 | MXene-GaN van der Waals metal-semiconductor junctions for high performance multiple quantum well photodetectors显示文摘A MXene-GaN-MXene based multiple quantum well photodetector was prepared on patterned sapphire substrate by facile drop casting.The use of MXene electrodes improves the responsivity and reduces dark current,compared with traditional Metal-Semiconductor-Metal(MSM)photodetectors using Cr/Au electrodes.Dark current of the device using MXene-GaN van der Waals junctions is reduced by three orders of magnitude and its noise spectral intensity shows distinct improvement compared with the traditional Cr/Au–GaN–Cr/Au MSM photodetector.The improved device performance is attributed to low-defect MXene-GaN van der Waals interfaces.Thanks to the high quality MXene-GaN interfaces,it is possible to verify that the patterned substrate can locally improve both light extraction and photocurrent collection.The measured responsivity and specific detectivity reach as high as 64.6 A/W and 1.93×1012 Jones,respectively,making it a potential candidate for underwater optical detection and communication.The simple fabrication of MXene-GaN-MXene photodetectors spearheaded the way to high performance photodetection by combining the advantages of emerging 2D MXene materials with the conventional III-V materials. | Lingzhi Luo Yixuan Huang Keming Cheng Abdullah Alhassan Mahdi Alqahtani Libin Tang Zhiming Wang Jiang Wu | 2021 | Light(Science & Applications)2021，10，10： | 1 |
| 6 | The chitinase gene (Bbchit1) from Beauveria bassiana enhances resistance to Cytospora chrysosperma in Populus tomentosa Carr.显示文摘 | Zhichun Jia Yimin Sun Li Yuan Qiaoyan Tian Keming Luo | 2010 | Biotechnology Letters2010，，9： | 1 |
| 7 | An improved procedure for Agrobacterium-mediated transformation of trifoliate orange (Poncirus trifoliata L. Raf.) via indirect organogenesis显示文摘 | Xiuping Zou Demou Li Xiaoying Luo Keming Luo Yan Pei | 2008 | In Vitro Cellular & Developmental Biology - Plant2008，，3： | 1 |
| 8 | Preparation and Properties of Polyacrylamide/Sodium Alginate Hydrogel and the Effect of Fe^(3+)Adsorption on Its Mechanical Performance显示文摘The preparation and application of functional hydrogels based on natural polysaccharides have always been a hot research topic.In this study,using acrylamide(AM)monomer,N,N'-methylene bisacrylamide(MBA)as crosslinking agent,potassium persulfate(K2S2O8)as initiator,in the presence of natural polysaccharide sodium alginate(SA),the PAM/SA hydrogel was prepared by free radical polymerization.Fourier transform infrared spectroscopy(FT-IR),swelling performance tests,scanning electron microscope(SEM),thermogravimetric analysis(TGA),UV-visible spectrophotometer,mechanical property measurements were carried out to analyze the composition,morphology,and performance of the hydrogels.The swelling behavior,dye adsorption performance,and the mechanical properties of PAM/SA hydrogels before and after Fe^(3+)adsorption were studied.The experimental results showed that the introduction of SA with 4.7%,7.8%,and 10.3%effectively improved the mechanical and dye adsorption properties of PAM composite hydrogels.The adsorption capacity of PAM/4.7%SA and PAM/10.3%SA hydrogels at equilibrium can reach 40.01 and 44.02 mg/g for methylene blue,which is higher than the value 13.58 mg/g of pure PAM hydrogel.The compressive strength of pure PAM hydrogel is 0.124 MPa.When the SA content is 4.7%,7.8%,and 10.3%,the compressive strength of the PAM/SA hydrogel was corresponding to 0.130 MPa,0.134 MPa,and 0.152 MPa,respectively.Fe^(3+)was introduced into the PAM/SA hydrogels,and PAM/SA/Fe^(3+)double-network hydrogels with excellent mechanical properties could be prepared by adjusting the SA content(4.7%,7.8%,and 10.3%),soaking time(1 h,2 h,3 h,4 h,5 h,6 h),and Fe^(3+)concentration(4.76%,7.41%,9.09%,and 13.04%).Under the same Fe^(3+)concentration of 9.09%and adsorption time of 4 h,the compressive strengths of the PAM/4.7%SA,PAM/7.8%SA,and PAM/10.3%SA hydrogels could reach 0.354 MPa,0.767 MPa,and 0.778 MPa,respectively. | Zheng Cao Yang Zhang Keming Luo Yinqiu Wu Hongxin Gao Junfeng Cheng Chunlin Liu Guoliang Tao Qingbao Guan Lei Zhang | 2021 | Journal of Renewable Materials2021，9，8： | 1 |
| 9 | Functional characterization of a cotton late embryogenesis-abundant D113 gene promoter in transgenic tobacco显示文摘 | Luo Keming Zhang Guofang Deng Wei | 2008 | Plant Cell Reports2008，27，4： | 1 |
| 10 | Woody plant cell walls:Fundamentals and utilization显示文摘Cell walls in plants,particularly forest trees,are the major carbon sink of the terrestrial ecosystem.Chemical and biosynthetic features of plant cell walls were revealed early on,focusing mostly on herbaceous model species.Recent developments in genomics,transcriptomics,epigenomics,transgenesis,and associated analytical techniques are enabling novel insights into formation of woody cell walls.Here,we review multilevel regulation of cell wall biosynthesis in forest tree species.We highlight current approaches to engineering cell walls as potential feedstock for materials and energy and survey reported field tests of such engineered transgenic trees.We outline opportunities and challenges in future research to better understand cell type biogenesis for more efficient wood cell wall modification and utilization for biomaterials or for enhanced carbon capture and storage. | Wei Li Ying-Chung Jimmy Lin Ying-Lan Chen Chenguang Zhou Shuang Li Nette De Ridder Dyoni M.Oliveira Lanjun Zhange Baocai Zhang Jack P.Wang Changzheng Xu Xiaokang Fu Keming Luo Ai-Min Wu Taku Demura Meng-Zhu Lu Yihua Zhou Laigeng Li Toshiaki Umezawa Wout Boerjan Vincent L.Chiang | 2024 | Molecular Plant2024，17，1： | 0 |
| 11 | A Dynamic Memory Allocation Optimization Mechanism Based on Spark显示文摘Spark is a distributed data processing framework based on memory.Memory allocation is a focus question of Spark research.A good memory allocation scheme can effectively improve the efficiency of task execution and memory resource utilization of the Spark.Aiming at the memory allocation problem in the Spark2.x version,this paper optimizes the memory allocation strategy by analyzing the Spark memory model,the existing cache replacement algorithms and the memory allocation methods,which is on the basis of minimizing the storage area and allocating the execution area according to the demand.It mainly including two parts:cache replacement optimization and memory allocation optimization.Firstly,in the storage area,the cache replacement algorithm is optimized according to the characteristics of RDD Partition,which is combined with PCA dimension.In this section,the four features of RDD Partition are selected.When the RDD cache is replaced,only two most important features are selected by PCA dimension reduction method each time,thereby ensuring the generalization of the cache replacement strategy.Secondly,the memory allocation strategy of the execution area is optimized according to the memory requirement of Task and the memory space of storage area.In this paper,a series of experiments in Spark on Yarn mode are carried out to verify the effectiveness of the optimization algorithm and improve the cluster performance. | Suzhen Wang Shanshan Geng Zhanfeng Zhang Anshan Ye Keming Chen Zhaosheng Xu Huimin Luo Gangshan Wu Lina Xu Ning Cao | 2019 | Computers, Materials & Continua2019，，8： | 0 |
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