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Cephus fumipennis Eversmann is a key insect pest of wheat crops in Qinghai, China. Its field population densities were surveyed by using both the back-loaded insect vacuum and a sweep net. Mean densities in township-level were calculated and a quantitative relation, ỹ =0,664 + 0,214 x, was established between the two sampling methods. The empirical relationship may be applicable in density monitoring and Integrated Pest Management program of the insect.
In order to overcome the defects of stronger subjectivity of common assessment methods of marine ecological environmental assessment, the entropy weight model was introduced. In the comprehensive assessment, because of different influence degrees of each index to the comprehensive assessment results, different improved measures can be adopted to increase policy ability. As Shannon information entropy has the advantages of objectivity and adaptability in determining weight value, it was applied to determine the weight value of each index in the comprehensive assessment model. Then the optimal and worst indexes were selected based on a double base point model. Through comparing the distance between the scheme point and double base points, the result of comprehensive assessment can be obtained. Then the model was employed to assess the ecological environment of a bay of China. Application results show the efficiency of this method.
Antimony (Sb) pollution has been of growing environmental concern. Little information is available on biosorption of Sb. In the present study, biosorption behavior and mechanisms of Sb(III) to the cyanobacterium Synechocystis sp. cells were investigated by batch experiments and FTIR analysis. Our study shows that Synechocystis sp. cells are a good adsorbent for Sb(III) with a sorption capacity of 4.68 mg・g⁻¹ dry weight adsorbent. The isothermal sorption data can be described by the Langmuir Isotherm and the Freundlich Isotherm. Several mechanisms were involved with biosorption of Sb to Synechocystis sp. cells and sorption to binding sites might be dominant. The sorption kinetics followed the pseudo-second order model. The adsorbed Sb is mainly located in extracellular polysaccharides (EPS) and within the cell, and a small proportion was adsorbed onto the cell wall. The proteins and polysaccharides in EPS and the polysaccharides on the cell are the main functional groups that are responsible for adsorption of Sb to Synechocystis sp. cells.
Focusing on the influence of wind and surface currents on local path planning in the marine environment, a multi-layered potential field (MPF) method is proposed to minimize the energy consumption of a water-jet propelled unmanned surface vehicle (USV). A synthetic environment framework that can incorporate the information of the base potential field layer and the environment layer is constructed first. This framework provides a base for minimizing the energy consumption of the water-jet propelled USV through proper force weighting. For the purpose of USV path planning, the traditional potential field method is extended by including the velocity information of the USV and the approached obstacles to avoid collisions with dynamic obstacles. The proposed method integrates kinematic control to prevent considering the vehicle as a point mass or rigid body. Finally, simulation and comparison experiments are performed to demonstrate the energy-saving efficiency of the proposed local path planning approach for the water-jet propelled USV
We studied the quantity and spatial and dynamic changes of land use and ecosystem service functions in Nanping City from 1995 to 2015 using of Landsat TM / ETM images in 1995, 2000, 2005, 2005, and 2015. The results show that the main land use types in the study area were forest land, cultivated land, and grassland, and the rapid growth rate of forest land was in sharp contrast with the decrease of cultivated land. In the conversion of six land use types, conversions among the forest land, cultivated land, and grassland were the most frequent. The forest was spatially schistose distribution and the grassland was clustered in the central and eastern parts, and the construction land was clustered to the central urban area, and the cultivated land was particularly broken, and the distribution pattern changes of the water area and unused land were not obvious. The dynamic changes of cultivated land, construction land, and unused land were more intense and their stability were worse, and the activity of land use in the study area was also increasing. The value of ecosystem services in Nanping was on the rise, and the contribution rate of forest ecosystem services was the highest, which accounted for more than 85% of the whole ecosystem service function, followed by grassland and cultivated land. The contribution rate of water area and unused land decreased less, while the contribution rate of unused land was minimal. Population is one of the driving factors that affect land use changes and the value of ecosystem services in Nanping.
The economic losses caused by postharvest fruits diseases have attracted global attention. Traditional chemical fungicide could not meet the need of humans. In recent years, microbial agent which has begun to take the place of chemical fungicide comes into people’s vision. The aim of this paper was to investigate the potential of Bacillus amyloliquefaciens strain BA3 for its biocontrol capability on gray mold decay of pears and its effect on postharvest quality of pears. Compared with other treatments, the inhibition effect on gray mold of washed cell suspension of B. amyloliquefaciens was the best. Consequently it was utilized in subsequent experiments. Spore germination and germ tube length of Botrytis cinerea was 18.72% and 12.85 μm treated with BA3, while the control group was 62.88% and 30.44 μm. We confirmed that increase of the concentration of B. amyloliquefaciens, improved the efficacy of BA3 in controlling gray mold decay of pears. Colonization variation of BA3 in wounds of pears was recorded. To begin with, the populations of B. amyloliquefaciens increased rapidly and remained stable. On the fourth day, there was a declining trend , after that the population increased to 4 × 10⁵ CFU/wound and remained stable. BA3 had no significant effect on mass loss, titratable acidity, firmness and total soluble solids of pears that were stored at 25°C for 7 days comparing with control group. However, the effect of B. amyloliquefaciens on ascorbic acid was significantly higher than that of the control group. Our study indicates that B. amyloliquefaciens has a potential as postharvest biocontrol agent on pears.
Variation of foliar stable Carbon Isotope Discrimination (CID Δ‰) and nutrient contents of Artemisia ordosica (Krasch) (semi-shrub species) and Caragana korshinskii (Kom.) (shrub species) were studied at the southeastern margin of the Tengger Desert, China. Foliar CID Δ, total phosphorus content (TP) and potassium content (K) in A. ordosica were markedly higher than in C. korshinskii while foliar total nitrogen content (TN) and water-use efficiency (WUE) (calculated from foliar CID Δ) in C. korshinskii were significantly higher than those in A. ordosica. There were significant and positive relationships between foliar CID Δ, TN and TP contents (P <0.001) in C. korshinskii, while in A. ordosica a strong and significant positive correlation existed between CID Δ and K content (P <0.001). Based on WUE, TN, TP, and K contents, as well as their relationships, we may conclude that in arid environments, the survival of C. korshinskii profits from its higher WUE, while the survival of A. ordosica from its higher TP and K contents in leaves. In addition, the correlations of foliar CID Δ values with TN and TP contents in C. korshinski and with K content in A. ordosica revealed that the water was one of the main factors limiting the absorption capacity for N and P in C. korshinskii, and for K in A. ordosica. While nutrient conditions were not the factors affecting the growth of C. korshinskii and A. ordosica in the study areas.
A full-length cDNA, SmPR10-1, encoding a pathogenesis-related class 10 protein, was isolated from Salvia miltiorrhiza, a well-known Chinese herbal plant. From the coding region of nucleotide sequence, the amino acid sequence can be predicted which contained conserved domain (K–A–X–E–X–Y) in the C-terminal helix found in most members of the PR10 protein family. Phylogenetic tree analysis indicated that the SmPR10-1 protein showed a sequence similarity which was much higher to dicot proteins than to other PR10 proteins. Prokaryotic expression of SmPR10-1 protein in fusion with a His-tag produced a 22 kDa protein in E. coli BL21 (DE3), which exhibited ribonuclease activity in vitro. The purified protein was used to assay antifungal activity and the results showed SmPR10-1 only inhibited the growth of Phytophthora infestans. The RT-PCR results showed that the SmPR10-1 was expressed in high transcript level in leaves, stalks and low levels in roots. This protein seems to involve in the plant active defense response through activation of the methyl jasmonate signaling pathway rather than salicylic acid or abscisic acid pathway.
Although the Qinghai-Tibetan Plateau (QTP) has experienced striking warming during the past century, information on how soil carbon (C) and nitrogen (N) pools of the alpine regions on the QTP respond to long-term warming is scarce. The aims of this study were to assess the response of soil organic C (SOC), total N (TN), labile C and N – including microbial biomass C (MBC) and N (MBN), inorganic N (Ninorg), dissolved organic C (DOC), and N (DON) – to 15-year experimental warming in an alpine region (Kobresia meadow and Potentilla scrubland), on the northeastern QTP using open-top chambers (OTCs). Fifteen-year experimental warming had no effect on SOC and TN concentrations and storage at 0-30 cm soil depth, either in Kobresia meadow or Potentilla scrubland habitat, which might be related to the low temperature increase and the unchanged water content. Long-term warming obviously affected soil labile C and N and their contributions to SOC and TN, especially in the meadow habitat, but the values were low, thus the variation of the labile C and N was not enough to influence total C and N storage. The C and N pools were shown to be controlled by different controlling factors, and scrubland was more stable than the meadow ecosystem confronting the change of environment.
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