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Despite the perceived importance of humin to forest ecosystem C sequestration, few studies have attempted to examine the responses to elevated temperature (ET, +2.5ºC) and elevated atmospheric CO2 concentration (EC, 700 ppm) on the chemical structures of humin. Solid-state 13C cross-polarization magic angle spinning nuclear magnetic resonance (13C CPMAS NMR) spectroscopy was applied to evaluate the 6-year effect of ET and EC on the chemical structure of humin under the coniferous forest ecosystems in the eastern Tibetan Plateau of China. Results showed that ET treatment decreased soil organic carbon (SOC), whereas EC and ETC treatment increased SOC. ET treatment decreased aromatic C and carbonyl C of humin while increasing alkyl C, the ratios of alkyl C/O-alkyl C, aliphatic C/aromatic C, and hydrophobic C/hydrophilic C. Compared with ET treatment, the ETC treatment had a similar but reduced impact on the chemical structure of humin, while EC had slightly and undetectable impact on the chemical structure of humin. The 6-year exposure to ET decreased SOC and changed the molecular structure of soil humin to be more alkyline and hydrophobic, and it was a protection mechanism to the sequestration and stability of organic C in soil.
Though fertilizers can improve grain yield, the trace heavy metals in fertilizers will also enter soil and migrate through food chains, which harbor ecological and health risks. This study was based on more than 30 years of location experiments. The objective was to investigate the effects of different fertilizer treatments on the bioavailability of heavy metals in Shajiang black soil. Total and available contents of Cu, Zn, Pb, and Cd in soil samples were determined by atomic absorption spectrophotometry (AAS), and were compared between different treatments by using single factor analysis of variance and least significant difference. Finally the bioavailability indices (BAIs) of heavy metals were calculated. The results show that after treatments of fertilizers, total contents of Cd, Cu, Pb, and Zn increased, but were all lower than China’s Soil Environment Quality Standards (SEQS, level II). Available Cu content was the highest after M treatment; available Zn contents were relatively low after all treatments; available Pb and available Cd contents were the highest after NP treatment. Under different treatments, the BAIs of each heavy metal were largely different. Bioavailability of a heavy metal was affected by soil properties and by its adsorption, desorption, complexation, precipitation, and dissolution in soil. The mean BAI of each metal ranked in the order of Cd>Pb>Cu>Zn; the available Cd and Pb were highly migratory, and thus can be absorbed and enriched by plants, and may finally threaten human health through food chains.
Background: The miRNA cluster miR-17-92 is known to act as an oncogene in various cancers. Members of this cluster were also found to be involved in some other pathological process, such as steatosis, which is a pivotal event in the initiation and progression of nonalcoholic fatty liver disease (NAFLD). This study aimed to explore whether miR-17, one of the most functional miRNAs in the miR-17-92 family, participates in the process of steatosis in hepatoma cells. Methods: We developed both a miR-17-expressing transgenic mouse model and a miR-17-expressing HepG2 cell model, the latter was established via stable transfection. Real-time PCR and western blot were applied to measure the expression levels of miR-17 and the potential target gene CYP7A1. The luciferase assay was used to confirm direct binding of miR-17 and CYP7A1. The oleic acid induction assay and Oil-Red-O staining were performed to support the determination of steatotic changes in HepG2 cell. Results: Extensive steatotic changes were observed in the livers of transgenic mice. Fewer were seen in the wild-type animals. CYP7A1 was confirmed as a target gene of miR-17, and the expression of CYP7A1 was found to be negatively regulated in both the transgenic mice liver cells and the miR-17-expressing HepG2 cells. CYP7A1 was found to participate in miR-17-induced steatosis, as its repressed expression in miR-17 HepG2 cells exacerbated steatotic change. Re-introduction of CYP7A1 into miR-17 HepG2 cell partially alleviated steatosis. Conclusions: miR-17 is a novel regulator of CYP7A1 signaling in hepatic lipid metabolism, suggesting a potential therapeutic approach for fatty liver.
Nigeria is facing some serious environmental challenges due to frequent oil spills, especially in the Niger Delta. Oil spills are one of the main sources of environmental contamination in the country. Daily oil spill incidents have polluted the air, soil, natural vegetation, farmlands, sources of drinking water, and fishing creeks. Multi end member spectral mixture analysis (MESMA) was used to calculate vegetation percentage inside each pixel of Landsat7 images before and after oil spill incidents to evaluate the negative influence of spilled oil on impacted areas' vegetation. 163 recorded oil spill incidents between 2011 and 2012 were investigated in the Rivers State, Nigeria for this purpose. Results revealed that 73% of studied spill-impacted areas have vegetation losses caused by oil spills. Recorded oil spill data were used to create a comprehensive spatial database using GIS to examine which types of data could be potential determinants for oil spill influence on Nigeria’s vegetation. Among fifteen different types of examined oil spill data; this study concluded that impacted area size, spilled oil volume, residual oil volume on site, impacted area environment, and response, recovery, and cleanup timing are major determinants for oil spill influence on the Niger Delta’s vegetation.
The green plant bug (Apolygus lucorum Meyer-Dür) is a key pest of Bt cotton in China. Along with biological control, chemical control is one of the most important strategies in A. lucorum Integrated Pest Management (IPM). The goal of this study was to evaluate the toxicity of eight conventional insecticides to A. lucorum and to assess the susceptibility of two generalist predators Chrysopa sinica (Jieder) and Propylaea japonica (Thunbery) to insecticides that are commonly used in A. lucorum management. Via glass-vial and leaf-dip bioassay, toxicity tests with selected insecticides at two different life-stages of A. lucorum indicated significant differences between the LD50 or LC50 values for these compounds within different insecticidal classes. Phenylpyrazole fipronil had the highest toxicity to 4th-instar nymphs and adults of A. lucorum, whereas neonicotinoid imidacloprid had the lowest toxicity among the insecticides. Females were more tolerant to insecticides than were males, as shown by the higher LD50 values for females. Furthermore, laboratory tests showed that endosulfan had the highest selectivity to C. sinica and P. japonica: the selective toxicity ratios (STRs) were superior to other tested insecticides, particularly imidacloprid, and were 5.396 and 4.749-fold higher than baseline STRs, respectively. From this study, we conclude that fipronil can potentially be used to efficiently control A. lucorum. An alternative control agent worth consideration is endosulfan, owing to its relative safety to non-targeted natural enemies.
It will be a new approach that BIM’s capital project lifecycle management (CPLM) applied to the yacht industry. This paper explored the feasibility of applying the principles and rationales of BIM for capital project lifecycle management in luxury yacht design, engineering, fabrication, construction and operation. The paper examined the premises and backbone technology of BIM. It then evaluated leading naval engineering and shipbuilding software applications and their development trends from the functional lens of BIM. To systematically investigate a BIM-based approach for capital project lifecycle management (CPLM) in the luxury yacht industry, the paper proposed and outlined an implementation framework. A case study and a student competition use case were discussed to delineate the core constituents and processes of the proposed framework. The case of BIM was reviewed. Through the domestic custom luxury yacht design and prototyping student competition, the application of this framework in educational research is demonstrated and the initial quantitative assessment of the framework is carried out. Conclusions: a BIM-based CPLM implementation framework can help the luxury yacht industry capitalize on the global transformation to an information-centric and data-driven new business paradigm in shipbuilding with integrated design, manufacturing and production
Group 3 late embryogenesis abundant proteins accumulate in maturing seeds, in which their expression correlates with desiccation tolerance. Group 3 proteins are also strongly associated with tolerance for abiotic stresses, such as high salinity, drought, cold, and osmotic stress in vegetative tissues. However, the precise function of these proteins remained obscure for more than 20 years. In this study, the structure of and available regulation information on Group 3 genes/proteins in Arabidopsis are reviewed. The function of Group 3 proteins in response to desiccation and the relationship between protein structure and function are also discussed.
Background. Minced meats undergo oxidative changes and develop rancidity more quickly than intact muscle since grinding exposes more of the muscle surface to air and microbial contamination. Due to concerns about toxicological safety of synthetic antioxidants, recent studies have put more focus on natural antioxidant compounds derived from food components. Material and methods. The effects of four natural antioxidants (vitamin E, carnosine, grape seed extract and tea catechins) on oxidative processes and metmyoglobin reducing activity in raw beef patties during refrigerated (4°C) storage were investigated and the results were compared with butylated hydroxyanisole treatment patties. The correlation of lipid oxidation, colour and metmyoglobin reducing activity of beef patties were also studied. Results. Samples treated with carnosine had the highest redness values on the eighth day. Tea catechins, vitamin E and grape seed extract showed higher protective effect against lipid oxidation than carnosine. Metmyoglobin reducing activity increased greatly in all samples during the storage. Significant correlation between redness value and lipid oxidation was demonstrated, while a weak correlation between metmyoglobin reducing activity and any other parameters was shown.
Screening and breeding of pollution-safe cultivars (PSCs) has become one of the most direct and cost-effective methods for reducing the health risks of heavy metal-contaminated soil. In this paper we identified and screened out cadmium (Cd)-pollution-safe pakchoi cultivars from 30 pakchoi genetype materials through preliminary screening experiments and re-screening experiments in field conditions. We found that in preliminary screening experiments, the Cd uptake displayed significant variability among the 30 selected pakchoi cultivaters grown in soil with a Cd concentration of 0.51 mg/kg. 11 out of the 30 pakchoi cultivars belonged to the low-Cd accumulated cluster classified by cluster analysis, which had the potential to be Cd-PSCs. The re-screening experiments under different Cd levels of contaminated soils in combination with the studies of the enrichment factors (EFs) and translocation factors (TFs) further confirmed the consistency and genotypic stability of the low-Cd accumulating traits of the potential Cd-PSCs. This study proves the feasibility of applying cluster analysis in the process of identifying PSCs.
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