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Nowadays, the contaminations generated by anthropogenic activities have had damaging effects on the life cycle of plants, particularly on the plants living in the vicinity of urban areas that are more associated with the life of people. Bamboo, as a local plant, is one of the most widely used plants in China. So, a pot experiment was conducted to investigate the effects of three HMs (Cu, Pb, and Zn) in four different concentrations (0 (for control), 500 mg/kg, 1000 mg/kg, and 200 mg/kg), with complete randomized design (CRD) by five replications for each treatment to measure the antioxidant enzymes, lipid per oxidation (LP), soluble protein (SP), gas exchange parameters, and morphological indexes in Sasa kongosanensis f. aureo – striatus. The results indicated that the antioxidant responses had an arc-shaped trend with various alterations in which POD and CAT first increase with low concentration of HMs (500 mg/kg) and then decrease with the increase of heavy metal (1000 mg/kg and 2000 mg/kg). Additionally, measuring of MDA content and soluble protein illustrated that MDA content and soluble protein increase with excess of HMs in different levels, and also the excess of HMs significantly decreases the photosynthesis properties. Moreover, the results obtained by morphological indices showed that low concentration of HMs increases both percentage of shoot length and percentage of emerge plants at all three kinds of HMs, but observe a downward trend with excess of heavy metal in 1000 mg/kg and 2000 mg/kg. Overall, in “Sasa kongosanensis f. aureo – striatus, results indicated that low concentration of HMs (500 mg/kg) can help the plant growth, while excess of HMs (1000-2000 mg/kg) alleviates the plant growth. On the other hand, Pb revealed the lowest antioxidant activity that leads to most membrane damage and eventually showed the lowest plant growth among the cases that HMs were tested, while Zn showed the most increasing plant growth in low concentration.
Cytoplasmic male sterility (CMS) is an important trait in rice (Oryza sativa L.) breeding because it provides a source for producing hybrid seeds. In rice CMS lines, ATPases involved in the oxidative phosphorylation complexes are believed to be dysfunctional due to the expression of rice CMS-related gene orf79. In the present study, a new type of CMS line named CMS-ZA (ZidaoA) was used. We found an orf79 homologous gene (named orfZ79) in three different rice lines (a CMS line, a maintainer line, and a hybrid). However, no detectable expression products of orfZ79 were found in the three lines. We evaluated the ATPase and NADH dehydrogenase activities of the three lines using in-gel catalytic assays. Our results show that the sterile line has intact ATPase activity, while NADH DHase activity is clearly decreased. To investigate NADH dehydrogenase deficiency, we measured NADH DHase activity in etiolated seedlings and green seedlings from the ZidaoA CMS sterile line and its corresponding maintainer line. We note that the NADH DHase activity of the sterile line was more deficient in green seedlings than that in etiolated seedlings. Our results show a possible role of NADH DHase deficiency to cause rice CMS.
Plant species growing in shallow-soil habitat are likely to experience water deficit especially in seasonally dry or arid regions. However, only scarce studies focused on their water-use strategies. The current study aimed to reveal water-use strategies of different species growing on continuous dolomite outcrops (a typical shallow-soil habitat) in subtropical China that relied on different water sources, and to investigate the differences between narrow endemic and widespread species, based on season variations in leaf δ¹³C values. Leaf samples of six plant species (Radermachera sinica, Sapium rotundifolium, Sterculia euosma, Schefflera octophylla, Alchornea trewioides, and Vitex negundo, in different life-forms and leaf phenologies) were collected for carbon isotope measurements in the wet and dry seasons, respectively. Contrary to the expectation, the evergreen big shrub species, S. octophylla, which always relied on deep water sources, exhibited the most positive δ¹³C values (high water-use efficiency, WUE), indicating more conservative water-use strategies. While the two deciduous small shrubs, A. trewioides and V. negundo, which always relied on shallow water sources, exhibited the most negative δ¹³C values (low WUE). This result was associated with their short life spans, indicating an opportunistic water-use strategy. Leaf δ¹³C values of almost all (except for S. octophylla) the selected species were significantly (P < 0.05) higher in the dry season than in the wet season. This indicated that it was a common strategy for species in rocky karst habitat to improve their WUE in dry season. Despite the similar water sources utilized by the selected three tree species, the widespread one (R. sinica) exhibited greater improvement in leaf δ¹³C values than the narrow endemic ones (S. rotundifolium and S. euosma). This suggested that the widespread tree species had more flexible water-use strategies. It was further speculated that broad spatial distribution of widespread species may contribute to their highly plastic responses to changes in environmental conditions rather than always maintaining high WUE.
Algae can increase pH and dissolved oxygen via photosynthesis and affect the wastewater treatment performance of high-rate algae ponds (HRAPs). Nine laboratory-scale HRAPs divided into three groups were constructed to treat synthetic wastewater via six-month experiments. Higher algae concentrations in the influent of HRAPs effectively promoted the wastewater treatment performance. Seasonal variation had a significant impact on algal growth. Summer tests exhibited a higher reduction of pollutants than autumn tests. The high-influent algae concentration group in summer (HRAP-A) largely reduced the TN by 52.7±3.0%, TP by 90.3±1.0%, and dissolved chemical oxygen demand (DCOD) by 99.0±1.0%. It outperformed the low influent algae concentration group in summer (HRAP-B) and was significantly higher than the high influent algae concentration group in autumn (HRAP-C). The appropriate operation and design of HRAPs contributed to efficient wastewater treatments.
The positive relationship between the number of species in an area and the size of the habitat studied (species-area relationship, SAR) is the foundation of ecological theory and the most studied issues in ecology. However, very few studies have addressed SARs and their relationships to functional group richness and the extent of habitat area studied. We analyzed SARs in different functional groups focusing on two types of tropical monsoon rainforests on Hainan Island, China. The number of trees, shrubs, lianas, all species, deciduous species, evergreen species, thorn species, non-thorn species, simple-leaved species, and compound-leaved species were strongly related to the size of the area studied in the two tropical monsoon rainforest communities. And the size of the area studied explained over 94% of the total variations in the number of families and other groups studied. No significant differences were found for the slope of the species-area curve (Z) of different functional groups in two tropical monsoon rainforest communities except for shrubs that were taller in the Terminalia hainanensis community (TC) than in Liquidambar formosana community (LC). In the comparison of different functional groups divided by the same principle in the same tropical monsoon rainforest, no significant difference was found for the value of Z for different functional groups except that Z for lianas were higher than for shrubs in LC. However, the Z of lianas was higher than that of trees and shrubs, and evergreen species and species without thorns had higher Z values than deciduous species and species with thorns. No significant differences were found between simple-leaved species and compound-leaved species in TC. The results indicated the SARs of different plant functional groups can be well-described by the power function, although their slopes differed significantly.
This paper mainly studies the longitudinal motion prediction method and control technology of high-speed catamaran using the active hydrofoils. To establish the longitudinal motion equations of the ship basing on the 2.5D theory. Using the CFD software to obtain the hydrodynamic data of the hydrofoil. Bring the hydrodynamic expression of hydrofoils into the longitudinal motion equations of the ship. Predicting the longitudinal motion of High-speed catamaran before and after added the hydrofoils. A specific catamaran has been predicted with this approach, the result indicates this approach is workable and this prediction approach provides the theoretical basis for assessing the stabilization ability of appendages and possess the engineering practical value
On the base of construction of a new type of cytoplasmic male sterile (CMS) line ZidaoA, we analyzed the editing of transcripts of mitochondrial ATP synthase subunit 9 gene (atp9) from CMS line and its maintainer line. With PCR, RT-PCR, and direct sequencing, complete nucleotide sequences were determined for the mitochondrial atp9 gene and its cDNA from two lines of purple rice type rice: CMS line Ying xiang A and its maintainer line Ying xiang B. The atp9 transcript of Ying xiang A was shown to have no editing sites and the transcript of Ying xiang B was shown to have two editing sites with changes affecting the amino acid sequence of the protein product. The editing of the atp9 transcript from Ying xiang B was found to change an arginine codon into a termination codon, shortening the protein of Ying xiang B to the ‘‘standard’’ size. And the Ying xiang A transcript, which has no termination codon, cannot be translated to a normal protein. The results demonstrate the important role of RNA editing in the production of the functional ATP9 subunit and suggest that RNA editing could be likely associated with cytoplasmic male sterility.
Reducing greenhouse gas emissions and governing pollutant emissions would cause real synergy. Therefore, China has proposed achieving the target of reducing fine particulate matter (PM₂.₅) concentrations to 35 ug/m3 , as it pollutes the most. The prioritized purpose of this dissertation is aimed at constructing a comprehensive framework by integrating the PM₂.₅ target, influencing factors, and countermeasures together to shed some new light on the PM₂.₅ governing problem. A computable general equilibrium (CGE) model containing a pollution abatement block is first introduced. Accordingly, four different scenarios about the PM₂.₅ target implementation plan are designed for analyzing the impacts on China’s macroeconomics, energy demand, and environmental quality, and we establish a PM₂.₅ system dynamics model in the principle of system dynamics theory afterward. Subsequently, the model offers six various countermeasures in terms of declining the concentration of PM₂.₅ on the basis of the causality diagram. Consequently, the scenario analysis and system simulation results illustrate that the decline in PM₂.₅ concentration at annual average rates of 3.07%, 4.61%, and 1.53% from 2016 to 2020, 2021 to 2025, and 2026 to 2030 is significantly beneficial for achieving the PM₂.₅ target. Additionally, three effective countermeasures could be approximately reaching the PM₂.₅ concentration target in 2030.
In this study, a methodology was presented to predict density stratified flows in the near-field of submerged bodies. The energy equation in temperature form was solved coupled with momentum and mass conservation equations. Linear stratification was achieved by the definition of the density as a function of temperature. At first, verifications were performed for the stratified flows passing a submerged horizontal circular cylinder, showing excellent agreement with available experimental data. The ability of the method to cope with variable density was demonstrated. Different turbulence models were used for different Re numbers and flow states. Based on the numerical methods proposed in this paper, the stratified flow was studied for the real scale benchmark DAPRA Suboff submarine. The approach used the VOF method for tracing the free surface. Turbulence was implemented with a k − ω based Detached Eddy Simulation (DES) approach. The effects of submarine speed, depth and density gradient on the free surface wave pattern were quantitatively analyzed. It was shown that, with the increasing of the speed of the submarine, the wavelength and wave height of the free surface wave were gradually increasing. The wave height of the free surface wave was gradually reduced as the submarine’s depth increased. Relative to the speed and submarine depth, the changes of the gradient density gradient have negligible effects on the free surface wave field
Algae growth and photosynthesis can be inhibited in high-rate algae ponds (HRAP) in cold climates. This study evaluated the feasibility and importance of polyester fiber strips (PFS) that can be applied to HRAP as growing sites for algae survival, thus enhancing HRAP performance. The results indicated that 42.0±2.0% TN, 86.0±1.0% TP and 99.0±1.0% DCOD were reduced in HRAP with high PFS amounts, which outperformed HRAP with low PFS amounts and was significantly higher than control. The positive role of PFS on algae biomass production could effectively remove organics and nutrient from wastewater.
Polygalacturonase-inhibiting proteins (PGIPs) are multifunctional proteins related to plant autoimmunity and belong to the plant extracellular leucine-rich repeat (eLRR) protein superfamily. PGIPs play a role in host defense in many plants. In the present study, a novel PGIP gene, PpPGIP was isolated from Pyrus pyrifolia Nakai cv Huobali. The nucleotide sequence of PpPGIP was highly homologous with PGIPs from other plant species and the protein encoded by PpPGIP has several conserved LRR domains. The putative protein PpPGIP was closely clustered with several PGIPs from horticultural plants on the phylogenetic tree. The constructed homology model of PpPGIP indicated that the main-chain conformation and the folding patterns of PpPGIP were highly similar to structural features of PvPGIP2 from Phaseolus vulgaris. The expression levels of PpPGIP in healthy tissue and organ of ‘Huobali’ were analyzed with RT-PCR, and PpPGIP accumulated a little in young leaves, but PpPGIP was expressed abundantly in the pericarp of ‘Huobali’ fruits. Furthermore, in order to verify the function of PpPGIP, the constitutive plant expression vector of PpPGIP was constructed and transferred into tobacco (Nicotiana tabacum L. cv Xanthi). The Southern blot and real-time PCR analyses demonstrated that the PpPGIP gene was integrated into the genome of the tobacco transformants and highly expressed in the transgenic lines. The antifungal activity of PpPGIP was detected in vitro plates, and the crude protein extract of transgenic tobacco plants inhibited the hyphal growth of Phomopsis sp., Alternaria sp., Penicillium sp., and Aspergillus niger in different degrees.
Anatase TiO₂ nanoparticles (NPs) are widely used in food products, capsules, toothpaste, and so on, so the kinds of NPs directly get in touch with human bodies. The potential effect of this kind of material on reproduction must be considered with the increase in infertility. Sixty ICR male mice were intragastrically treated with dosages of 0, 10, 50, and 100 mg kg⁻¹ body weight (BW) anatase TiO₂ NPs to investigate the male reproductive toxicity of the NPs. Sperm quality, morphological changes in mice testes, and oxidative damage indexes were investigated in this study. Results showed that anatase TiO₂ NPs could lead to sperm malformation and increased rate of sperm cell micronucleus. These NPs also reduced the germ cell number and led to spherospermia, interstitial glands vacuole, malalignment, and vacuolization of spermatogenic cells in mice testes. Testicular cells accumulated reactive oxygen species when the mice were intragastrically administrated with TiO₂ NPs. Superoxide dismutase activity decreased, and the malondialdehyde content increased in the TiO₂ NP-treated groups. Anatase TiO₂ NPs exerted potential toxic effects on male reproduction, so the widespread application of this kind of NP in food products needs to be regulated.
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