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1

Assessment of heavy metals contamination in near-surface dust

100%
Yang Z., Ge H., Lu W., Long Y.
Polish Journal of Environmental Studies
|
2015
|
tom 24
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nr 4
As a result of the continuous urbanization and industrialization in China over the last few decades, heavy metals have been continuously emitted into urban environments and now pose serious threats to human health. In the present study, an extensive urban near-surface dust survey was conducted in Changchun, China, to evaluate the current status of heavy metal contamination in urban dust and to identify the potential sources. A total of 232 samples were collected and the levels of Cu, Pb, Zn, Cd, Hg, As, Cr, and the major elements were then determined. The results indicated that the urban dusts were enriched with metals, particularly Cu, Cd, Zn, Pb, and Hg. Principal component analysis (PCA) was employed to identify sources of heavy metals, and the results revealed distinctly different associations among the trace metals and the major elements in the urban dusts. The concentrations of Cr and As appeared to be controlled by natural factors. Cu and Pb were mainly from vehicle emissions. Zn primarily come from traffic sources, especially vehicle tires. Additionally, Hg primarily originated from coal combustion, while Cd was mainly associated with industrial sources. A revised pollution index for each metal and a Nemerow integrated pollution index (NIPI) of the seven metals were attributed to each sampling site to assess the degree of metal contamination. The results showed that the pollution indexes (PI) of each metal are not especially high. However, a significant degree of metal pollution exists in some urban dusts in Changchun, particularly for Cu, Cd, Zn, and As. The mean value of the Nemerow integrated pollution index (NIPI) of the seven metals also indicated that urban dusts in Changchun city were classified as having moderate levels of pollution. However, it should be noted that about 11% of all samples had a NIPI value above 3, suggesting a high level of contamination by metals. These findings indicate that more attention should be paid to metal pollution of the urban dusts in Changchun in the future.
2

Application of dual - response surface methodology and radial basis function artificial neural network on surrogate model of the groundwater flow numerical simulation

88%
Yi Y., Lu W., Hong D., Liu H., Zhang L.
Polish Journal of Environmental Studies
|
2017
|
tom 26
|
nr 4
The surrogate model is an effective way to connect the simulation and optimization models in groundwater flow numerical modeling; it could overcome the limitations of embedding and calling simulation models in the optimization model by conventional methods, which greatly reduces the computational load caused by directly calling the simulation model in the solving process of the optimization model. In this paper, the dual-response surface method and radial basis function artificial neural network method were applied to establish the surrogate model of groundwater flow numerical simulation in Jinquan Industrial Park, Inner Mongolia, China. The Latin hypercube sampling method was used to determine random pumping load of the five pumping wells, which were taken as the input data groundwater flow numerical simulation model for calculating 10 observation wells drawdown data sets (output data sets). Based on the input and output data sets, the dual-response surface method and radial basis function artificial neural network method were used to establish the surrogate model of groundwater simulation model, and the validity of surrogate models were comparatively tested. The results showed that both the results of two surrogate models fit well with the results of the simulation model, which indicates that two surrogate models were capable of approaching the groundwater flow numerical simulation model; compared with the dual response surface model, the RBF neural network model had more advantages in terms of sample size requirements, fitting the accuracy of simulation results.
3

Effect of hydroxyl radical on the scission of cellular wall polysaccharides in vitro of banana fruit at various ripening stages

76%
Cheng G., Duan X., Yang B., Jiang Y., Lu W., Luo Y., Jiang W.
Acta Physiologiae Plantarum
|
2008
|
tom 30
|
nr 2
Fruit ripening is generally attributed to disassembly of cellular wall, particularly due to solubilisation and depolymerisation of pectin and hemicellulose. Experiments were conducted to test effects of hydroxyl radicals (OH) on the scission of cellular wall polysaccharides from pulp tissues of banana fruit at different ripening stage. Cellular wall materials were isolated from pulp tissues of banana fruit at different ripening stages. Two pectic fractions, water soluble pectin (WSP) and acid soluble pectin (ASP), and two hemicellulosic fractions, 1 M KOH soluble hemicellulose (HC1) and 4 M KOH soluble hemicellulos (HC2), were obtained from the cellular wall materials from pulp tissues, respectively. Effects of OH induced by the Fenton reaction on the scission of pectin and hemicellulose in vitro were investigated. As fruit ripening progressed, the sugar components of the WSP, HC1 and HC2 attacked by OH showed obvious molecular-mass downshifts. Thus, OH caused the disassembly of polysaccharides (WSP, ASP, HC1 and HC2) from cellular walls of pulp tissues of banana fruit, demonstrated by the reduced molecular mass distribution. Moreover, OH production in pulp tissues increased significantly as banana fruit ripened, which further help account for the role of OH in accelerated fruit ripening.
4

Interaction of abscisic acid and auxin on gene expression involved in banana ripening

76%
Lu W., Mao L., Chen J., Han X., Ren X., Ying T., Luo Z.
Acta Physiologiae Plantarum
|
2018
|
tom 40
|
nr 03
5

Expression pattern and function of wheat mitogen-activated protein kinase (MPK) cascade genes under micronutrient-deprived conditions

76%
Yao S., Wang Y., Yang T., Kou F., Lu W., Xiao K.
Acta Physiologiae Plantarum
|
2017
|
tom 39
|
nr 01
6

Cloning a DNA marker associated to wheat scab resistance

76%
Yu G., Ma H., Xu Z., Ren L., Zhou M., Lu W.
Journal of Applied Genetics
|
2004
|
tom 45
|
nr 1
7

Enriched environment increases the total number of CNPase positive cells in the corpus callosum of middle-aged rats

64%
Zhao Y.-Y., Shi X.-Y., Qiu X., Zhang L., Lu W., Yang S., Li C., Cheng G.-H., Yang Z.-W., Tang Y.
Acta Neurobiologiae Experimentalis
|
2011
|
tom 71
|
nr 3
It had been reported that enriched environment was beneficial for the brain cognition, neurons and synapses in cortex and hippocampus. With diffusion tensor imaging (DTI), several studies recently found the trained-induced larger corpus callosum. However, the effect of enriched environment on the oligodendrocytes in corpus callosum has not been explored with the unbiased stereological methods. In current study, the effect of enriched environment on the total number of 2',3'- cyclic nucleotide 3'-phosphodiesterase (CNPase) positive cells in middle-aged rat corpus callosum was investigated by means of immunohistochemical techniques and the unbiased stereological methods. We found that, when compared to standard rats, the spatial learning capacity of enriched-environment rats was significantly increased. The total number of the CNPase positive cells in the corpus callosum of enriched-environment middle-aged rats was significantly increased when compared to standard rats. The present study provided, to the best of our knowledge, the first evidence of environmental enrichment-induced increases in the total number of CNPase positive cells in the corpus callosum of middle-aged rats.
8

TaPT2, a high-affinity phosphate transporter gene in wheat (Triticum aestivum L.), is crucial in Pi uptake under phosphorus deprivation

64%
Guo C., Guo L., Li X., Gu J., Zhao M., Duan W., Ma C., Lu W., Xiao K.
Acta Physiologiae Plantarum
|
2014
|
tom 36
|
nr 06
Acquisition of inorganic phosphate (Pi) by plant roots is performed by phosphate transporters (PTs) located at the cytoplasmic membranes of epidermal cells and root hairs. A Triticum aestivum PT gene denoted as TaPT2 was functionally characterized in this study. TaPT2 is highly similar to TtPT2 and HvPT2, two PHT1 family genes in T. aestivum/Thinopyrum intermedium and barley, respectively. TaPT2 is 1,802 bp long at the cDNA level; it encodes a 525-amino acid polypeptide with a molecular weight of 57.5 kDa and an isoelectric point of 8.65. TaPT2 contains 12 conserved membrane-spanning domains and is transported to the cytosolic membrane after endoplasmic reticulum sorting. Functional complement analysis revealed that TaPT2 endowed Pi transporter activities in a yeast mutant that is defective in Pi uptake, with highaffinity Pi acquisition. TaPT2 transcripts were specifically detected in the roots. The transcripts were upregulated under Pi deprivation and downregulated under Pi sufficiency. These results suggest that TaPT2 expression is associated with external Pi concentration. Transgene analysis revealed that TaPT2 overexpression or knockdown did not regulate plant dry mass production, Pi acquisition, and photosynthetic capacity under Pi sufficiency. Under Pi deprivation, TaPT2 overexpression increased plant dry mass accumulation, total P content per plant, and photosynthetic efficiencies, whereas TaPT2 downregulation reduced plant dry mass, accumulative P amount, and photosynthetic parameters. These results collectively suggest that TaPT2 is a high-affinity PHT1 member that has important functions in mediating plant Pi uptake under Pi deprivation. TaPT2 can serve as a useful gene resource for the improvement of phosphorus use efficiency in cereals under Pi deprivation.
9

The impacts of crustacean zooplankton on a natural ciliate community: a short-term incubation experiment

64%
Li J., Yang K., Chen F., Lu W., Fang T., Zhao X., Li H., Cui K.
Acta Protozoologica
|
2017
|
tom 56
|
nr 4
10

Integrated miRNAome and mRNAome analysis identifies candidate genes that mediate testis development promoted by vitamin E in sheep

64%
Gao Y., Lu W., Qu Y., Jian L., Diao Z., Xiu P., Machaty Z., Luo H.
Animal Science Papers and Reports
|
2020
|
tom 38
|
nr 3
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