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Xu J.,University of Florida | Jia Z.,Hebei Academy of science | Knutson M.D.,University of Florida | Leeuwenburgh C.,University of Florida
International Journal of Molecular Sciences | Year: 2012

Aging is associated with disturbances in iron metabolism and storage. During the last decade, remarkable progress has been made toward understanding their cellular and molecular mechanisms in aging and age-associated diseases using both cultured cells and animal models. The field has moved beyond descriptive studies to potential intervention studies focusing on iron chelation and removal. However, some findings remain controversial and inconsistent. This review summarizes important features of iron dyshomeostasis in aging research with a particular emphasis on current knowledge of the mechanisms underlying age-associated disorders in rodent models. © 2012 by the authors; licensee MDPI, Basel, Switzerland.

Liu R.,Nanjing Agricultural University | Liu R.,Nanjing Normal University | Chen L.,Nanjing Agricultural University | Chen L.,Zhejiang Academy of Agricultural Sciences | And 6 more authors.
Molecular Plant-Microbe Interactions | Year: 2011

AtMYB44 is a transcription factor that functions in association with the ethylene-signaling pathway in Arabidopsis thaliana. The pathway depends on ETHYLENE INSENSITIVE2 (EIN2), an essential component of ethylene signaling, to regulate defense responses in the plant following treatment with HrpNEa, a harpin protein from a bacterial plant pathogen. Here, we show that AtMYB44 regulates induced expression of the EIN2 gene in HrpNEa-treated Arabidopsis plants. A HrpNEa and ethylene-responsive fragment of the AtMYB44 promoter is sufficient to support coordinate expression of AtMYB44 and EIN2 in specific transgenic Arabidopsis. In the plant, the AtMYB44 protein localizes to nuclei and binds the EIN2 promoter; the HrpNEa treatment promotes AtMYB44 production, binding activity, and transcription of AtMYB44 and EIN2. AtMYB44 overexpression results in increased production of the AtMYB44 protein and the occurrence of AtMYB44-EIN2 interaction under all genetic backgrounds of wild-type Arabidopsis and the etr1-1, ein2-1, ein3-1, and ein5-1 mutants, which have defects in the ethylene receptor ETR1 and the signal regulators EIN2, EIN3, and EIN5. However, AtMYB44 overexpression leads to enhanced EIN2 expression only under backgrounds of wild type, ein3-1, and ein5-1 but not etr1-1 and ein2-1, suggesting that ethylene perception is necessary to the regulation of EIN2 transcription by AtMYB44. © 2011 The American Phytopathological Society.

Zhao H.-Y.,Hebei Academy of science | Li G.-X.,Shijiazhuang University of Economics | Zhang H.-L.,Zhejiang University | Xue Y.,South China Normal University
International Journal of Machine Learning and Cybernetics | Year: 2016

In many real application, the volume of time series data increases seriously. How to store and process data becomes more interesting and challenge things. Effective representations can make storage less, processing more easily. In this paper, we contribute to construct a new piecewise linear approximation algorithm for segmenting online time series with error bound guarantee. To beat our targets, we combine a disconnected segment strategy into Feasible Space Window method, and to test our algorithm, we compare with algorithms that adopts the above strategies on both real and synthetic data sets. The time complexity of our algorithm is O(n) and the number of segments is smaller than FSW algorithm on all tested data sets. © 2014, Springer-Verlag Berlin Heidelberg.

Bai H.,CAS Institute of Geographical Sciences and Natural Resources Research | Bai H.,University of Chinese Academy of Sciences | Tao F.,CAS Institute of Geographical Sciences and Natural Resources Research | Tao F.,Natural Resources Institute Finland Luke | And 4 more authors.
Climatic Change | Year: 2016

Using the detailed field experiment data from 1981 to 2009 at four representative agro-meteorological experiment stations in China, along with the Agricultural Production System Simulator (APSIM) rice-wheat model, we evaluated the impact of sowing/transplanting date on phenology and yield of rice-wheat rotation system (RWRS). We also disentangled the contributions of climate change, modern cultivars, sowing/transplanting density and fertilization management, as well as changes in each climate variables, to yield change in RWRS, in the past three decades. We found that change in sowing/transplanting date did not significantly affect rice and wheat yield in RWRS, although alleviated the negative impact of climate change to some extent. From 1981 to 2009, climate change jointly caused rice and wheat yield change by −17.4 to 1.5 %, of which increase in temperature reduced yield by 0.0–5.8 % and decrease in solar radiation reduced it by 1.5–8.7 %. Cultivars renewal, modern sowing/transplanting density and fertilization management contributed to yield change by 14.4–27.2, −4.7– −0.1 and 2.3–22.2 %, respectively. Our findings highlight that modern cultivars and agronomic management compensated the negative impacts of climate change and played key roles in yield increase in the past three decades. © 2015, Springer Science+Business Media Dordrecht.

Xu C.,Hebei Academy of science
Wei sheng wu xue bao = Acta microbiologica Sinica | Year: 2011

Quorum-sensing (QS) is a regulatory mechanism with which bacteria regulate the gene expression according to their population density. Pseudomonas aeruginosa regulates the expression of multiple genes via a hierarchical quorum-sensing cascade through LasR and RhlR and their cognate signal molecules N-(3-oxododecanoyl)-L-homoserine lactone (30-C12-HSL) and N-(butanoyl)-L-homoserine lactone (C4-HSL). It aims to explore the regulation of QS on biosynthesis of polyhydroxyalkanoates (PHA) in P. aeruginosa. Wild-type P. aeruginosa PA01 and its QS mutants were used to investigate the effects of quorum-sensing on biosynthesis of PHA by GC and real-time PCR at physiological and molecular level. After treated with QS signal molecule synthesis inhibitor azithromycin, the accumulation of PHA significantly decreased in P. aeruginosa PA01 and its QS mutant strains. The content of PHA in C4-HSL synthase gene rhlI mutant strain PA0210 had no significant difference compared with that of the wild type. However, the PHA contents were significantly affected in 30C12-HSL synthase gene lasl mutant strain PA055, 30C12-HSL transcriptional regulator gene lasR mutant strain PA056 and lasI/lasR double mutant strain PA057. PHA synthase gene phaC1 expression exhibited a significant reduction in lasI mutant and lasR mutant strains. 30C12-HSL signal molecules complementary experiment shows that the expression of phaC1 can be recovered to the level of the wild type, but the synthesis of PHA is only partially restored in lasI mutant strain. The results implicates that lasI/lasR system might be involved in the regulation of intracellular PHA biosynthesis in P. aeruginosa PA01.

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