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Growth and nutrient accumulation of Phragmites australis in relation to water level variation and nutrient loadings in a shallow lake

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Journal of Environmental Sciences 2013年第1期25卷 16-25页

作者： Ying zhao Xinghui xia Zhifeng Yang State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal University

Shallow lake eutrophication is a global environmental issue. This study investigated the effects of water level variation and nutrient loadings on the growth and nutrient accumulation of Phragmites australis （reed） by field samplings in Baiyangdian Lake, the largest shallow lake of northern China. The field samplings were conducted in two sites of different nutrient loadings during the whole growth period of reeds, and three types of zones with different water depths were chosen for each site, including the terrestrial zone with water level below the ground, the ecotone zone with the water level varying from belowground to aboveground, and the submerged zone with water level above the ground. The result showed that reed growth was more limited by water level variation than nutrient loadings. The average stem lengths and diameters in terrestrial zones were about 26.3%-27.5% and 7.2%-12.0% higher than those in submerged zones, respectively. Similarly, the terrestrial status increased the aboveground biomass of reeds by 36.6%-51.8% compared with the submerged status. Both the nutrient concentrations and storages in the aboveground reeds were mainly influenced by the nutrient loadings in surface water and sediment rather than the water level variation of the reed growth environment, and the nutrient storages reached their maxima in late August or early September. It was observed that the maximum nitrogen storage occurred in the terrestrial zone with higher nutrient loadings, with the value of 74.5 g/m2. This study suggested that water level variation and nutrient loadings should be considered when using reeds to control and remediate eutrophication of shallow lakes.

关键词： water level variation nutrient loadings Phragmites australis reed growth nutrient accumulation

Improved RIP-based performance guarantees for multipath matching pursuit

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Science China(Information Sciences) 2018年第10期61卷 173-186页

作者： Juan zhao xia BAI Ran TAO School of Information and Electronics Beijing Institute of Technology Beijing Key Laboratory of Fractional Signals and Systems Beijing Institute of Technology

The multipath matching pursuit(MMP) is a generalization of the orthogonal matching pursuit(OMP), which generates multiple child paths for every candidate in each iteration and selects the candidate having the minimal residual as the final support set when iteration ends. In this paper we analyze its performance in both noiseless and noisy cases. The restricted isometry property(RIP)-based condition of MMP that ensures accurate recovery of sparse signals in the noiseless case is derived by using a simple technique. The performance guarantees of the MMP for support recovery in noisy cases are also *** is shown that under certain conditions on the RIP and minimum magnitude of nonzero components of the sparse signal, the MMP will exactly recover the true support of the sparse signal in cases of bounded noises and recover the true support with a high probability in the case of Gaussian noise. Our bounds on the RIP improve the existing results.

关键词： compressed sensing(CS) sparse signal reconstruction multipath matching pursuit(MMP) support recovery restricted isometry property(RIP)

Study of large medical equipment allocation in Xuzhou

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第12期8卷 881-884页

作者： MIAO Chun-xia ZHUO Lang GU Yu-ming qin zhao-hui School of Public Health Xuzhou Medical College Xuzhou 221002 China

Objective: To investigate the allocation and management of large medical equipment (LME) in Xuzhou, Jiangsu Province, China, in order to make the best use of LME to meet the medical needs of local people. Methods: The research collected data from all hospitals that have LME in Xuzhou using questionnaire; 38 (97.4%) hospitals returned the questionnaire. Results: In Xuzhou, there are a total of 71 pieces of LME, each serving 126 600 people in an area of 163 km2. Sixty-two percent of them are allocated in urban areas, with Gini coefficient at 0.52, indicating imbalance and biased allocation of LME. Conclusion: The al- location of LME in Xuzhou is out of control and unfairly allocated.

关键词： Large medical equipment (LME) Computerized tomography (CT) Allocation Gini coefficient

Thermal behaviors and heavy metal vaporization of phosphatized tannery sludge in incineration process

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Journal of Environmental Sciences 2008年第9期20卷 1146-1152页

作者： TANG, Ping zhao, Youcai xia, Fengyi State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University Shanghai 200092 China Department of Life and Environmental Science Wenzhou University Wenzhou Zhejiang 325007 China

The high concentration of heavy metal (Cu, Cr, Zn, Pb) in tannery sludge causes severe heavy metal emissions in the process of incineration. In the present investigation, the tannery sludge was treated with 85% phosphoric acid before the incineration process in the tube furnace to control the heavy metal emissions. The thermal behavior and heavy metal vaporization of pre-treated tannery sludge were investigated, and X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were also implemente...

关键词： tannery sludge thermal behavior heavy metal vaporization phosphatation

Effect of mixture sowing on biomass allocation in the artificially-planted pastures, Southeastern Tibetan

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Journal of Mountain Science 2019年第1期16卷 54-63页

作者： CHEN Fan xia Hao qin xiao-jing Power China Guiyang engineering corporation limited Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and Environment Chinese Academy of Science University of Chinese Academy of Sciences

Artificial planting is an important measure to promote the restoration of degraded grassland and protect the ecological environment. The objectives of the current study were to investigate the allocation pattern between aboveground biomass(AGB) and belowground biomass(BGB) in different seeding types of artificially-planted pastures. We explored the variation in biomass and the relationship between above-and belowground biomass in four artificiallyplanted pastures with one species from Elymus nutans Griseb(EN, perennial), Elymus sibiricus Linn(ES, perennial), Medicago sativa Linn(MS, perennial), and Avena sativa Linn(AS, annual) and in six artificially-planted communities with mixtures of two species by seeding ratio 1:1 from the abovementioned grasses(EN + AS, MS + AS, EN + ES, MS + EN, MS + ES, AS + ES) in 2015 and 2016. The results showed that E. nutans is the most productive species with the highest biomass production among the single crops. MS + ES was the most productive group in 2015, while the group with the highest biomass production changed to AS + ES in 2016. AGB was positively correlated to BGB in the surface soil layer in the first year, but positively related to BGB in the subsoil layer in the second year. In the early stageof artificial grassland succession, plants allocated more biomass to aboveground parts, with a root to shoot(R/S) ratio of 1.98. The slope of the log-log relationship between AGB and BGB was 1.07 in 2016, which is consistent with the isometric theory. Different sowing patterns strongly affected the accumulation and allocation of biomass in artificiallyplanted grassland, E. sibiricus was the suitable plant in the alpine regions, which will be conducive to understanding vegetation restoration and plant interactions in the future.

关键词： Artificial grassland Aboveground biomass Belowground biomass Mono seeding Mixed seeding Elymus

烟酰胺磷酸核糖转移酶与糖尿病肾脏疾病关系的研究进展

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医学综述 2025年第1期31卷 80-86页

作者：沈倩秦宇婷赵鼎盐城师范学院药学院江苏盐城224002 南京中医药大学附属盐城中医院盐城市中医院肿瘤科江苏盐城224000

烟酰胺磷酸核糖转移酶(Nampt)在体内分布广泛,通过多种途径发挥不同的生物学作用。细胞内Nampt作为烟酰胺腺嘌呤二核苷酸生物合成的限速酶在机体能量代谢、细胞存活及死亡中发挥重要作用;细胞外Nampt作为细胞因子,参与调控糖脂代谢、炎... 详细信息

烟酰胺磷酸核糖转移酶(Nampt)在体内分布广泛,通过多种途径发挥不同的生物学作用。细胞内Nampt作为烟酰胺腺嘌呤二核苷酸生物合成的限速酶在机体能量代谢、细胞存活及死亡中发挥重要作用;细胞外Nampt作为细胞因子,参与调控糖脂代谢、炎症反应、氧化应激、血管损伤、细胞自噬等病理生理过程。Nampt在糖尿病肾脏疾病(DKD)肾组织和血清中表达增加,其与DKD的发生发展密切相关,可加重代谢紊乱、诱导炎症纤维化、介导血管内皮损伤、增强氧化应激反应等。DKD发病机制复杂,揭示并阐明Nampt在其不同阶段的生物作用具有重要意义。

关键词：糖尿病肾脏疾病烟酰胺磷酸核糖转移酶炎症纤维化氧化应激血管损伤

Functional analyses of an E3 ligase gene AIP2 from wheat in Arabidopsis revealed its roles in seed germination and pre‐harvest sprouting

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Journal of Integrative Plant Biology 2014年第5期56卷 480-491页

作者： Dong-Yao Gao zhao-Shi Xu Yi He Yong-Wei Sun You-Zhi Ma Lan-qin xia Institute of Crop Sciences/The National Key Facility for Crop Gene Resources and Genetic Improvement the Chinese Academy of Agricultural Sciences (CAAS) Agricultural and Sideline Base Unit 65426 of the People’s Liberation Army

Pre‐harvest sprouting（PHS） seriously affects wheat yield and quality of the grain. ABI3 is a key factor in the activation of seed development and repression of germination in Arabidopsis. An ABI3‐interacting protein（AIP2） could polyubiquitinate ABI3, impair seed dormancy and promote seed germination in Arabidopsis. In this study,two wheat AIP2 genes, TaAIP2A and TaAIP2B, were *** localization assay and yeast two‐hybrid analysis revealed that TaAIP2A and TaAIP2B may function through interaction with wheat Viviporous‐1（TaVp1）. The transcripts TaAIP2A and TaAIP2B were more abundant in wheat PHS susceptible cultivars than that of resistant ones, and decreased gradually following seed development. Expression of TaAIP2A and TaAIP2B in Arabidopsis aip2‐1 mutant lines resulted in earlier flowering, promotion of seed germination,and reduced ABA sensitivity, respectively, somehow mimicking the phenotype of the wild type, with TaAIP2B having a stronger role in these aspects. Furthermore, the expression ofupstream genes ABI1 and ABI2 were upregulated, whereas that of downstream genes ABI3 and ABI5 were downregulated in both TaAIP2A and TaAIP2B complemented lines upon ABA treatment. These results suggested that wheat AIP2s could negatively regulate the ABA signaling pathway and play important roles in seed germination, and thus wheat PHS resistance finally.

关键词： ABA responsiveness AIP2 Arabidopsis E3 ligase functional analysis pre‐harvest sprouting Triticum aestivum L

2013-2023年广安市HIV感染者及AIDS患者死亡病例分析

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中国麻风皮肤病杂志 2025年第1期41卷 23-28页

作者：田彩虹秦小佳张军龚毅赵智蓉广安市疾病预防控制中心四川广安638000 四川省疾病预防控制中心四川成都610000 昆明市第三人民医院云南昆明650200

收集2013-2023年国家艾滋病综合防治信息系统报告的广安市HIV/AIDS病例资料,运用Logistic回归模型分析HIV/AIDS病例死亡的影响因素。结果示广安市2013-2023年累计报告HIV/AIDS病例8803例,死亡2489例,病死率为28.27%。死亡病例中,AIDS占6... 详细信息

收集2013-2023年国家艾滋病综合防治信息系统报告的广安市HIV/AIDS病例资料,运用Logistic回归模型分析HIV/AIDS病例死亡的影响因素。结果示广安市2013-2023年累计报告HIV/AIDS病例8803例,死亡2489例,病死率为28.27%。死亡病例中,AIDS占61.91%,男性占86.86%,确诊年龄在55岁及以上占68.62%,农民占72.32%,有配偶占55.56%,小学以下文化程度占74.25%,异性性传播占95.22%,医疗机构来源占73.04%,首次CD4^(+)T淋巴细胞未查者和小于200个/μL占62.43%,未行抗病毒治疗(antiretroviral therapy,ART)和ART不及时者占66.05%。多因素Logistic回归分析结果显示,HIV、女性、有配偶、来源于非医疗机构、确诊年龄<35岁、治疗及时的病例死亡概率较低;文化程度为小学及以下、确诊年龄≥55岁、首次就诊未检查CD4^(+)T淋巴细胞、未治疗的病例死亡概率较高。不论是HIV感染者还是AIDS患者,治疗组存活时长显著高于未治疗组(P<0.05)。

关键词：获得性免疫缺陷综合征死亡病例特征抗病毒治疗

SOCIAL TAGGING DYNAMICS UNDER SYSTEM RECOMMENDATION AND RESOURCE MULTIDIMENSIONALITY

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Journal of Systems Science and Systems Engineering 2016年第3期25卷 271-286页

作者： Haoxiang xia xiaowei zhao Huiyu Liu Institute of Systems Engineering Dalian University of Technology Dalian 116024 China School of Software Technology Dalian University of Technology Dalian 116620 China Dalian Branch of China Unicorn Ltd. Dalian 116001 China

Social tagging systems have attracted plenty of research endeavors recently. The dynamic models of tag generation or tag usage are one of the key subjects of inquiry. However, the existing models do not well explain the ＂staged＂ power-law distribution of tag usage frequencies as observed in various social tagging systems. To cope with this, a new tag-generation model is proposed in this paper, which is based on a preferential selection mechanism influenced by the combinatorial effects of system recommendation and resource multidimensionality. Furthermore, to validate the model, the simulative results under different parameter combinations are compared with the distributions of tag usage frequencies in datasets from three famous social tagging systems, namely ***, *** and Flickr. For different categories of resources of the three systems, three tag usage patterns can be identified, namely the power-law distribution with two plateaus, the power-law distribution with one plateau, and the standard power-law distribution. All the three patterns can be well fitted and explained by the proposed model.

关键词： Social tagging systems tag usage patterns dynamic model