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The traditional efficiency evaluation model considering undesirable outputs is only able to calculate the efficiency of the overall value of the decision-making units. This paper puts forward a new environmental efficiency evaluation based on the proper slack-based measurement (PSBM) model, which can give the efficiency values of the inputs, desirable outputs, and undesirable outputs. The results from the new model are not only highly correlated with SBM-based evaluation results, but also coincide with reality, which can be used to test the effectiveness of the new model. Our model provides more information for environmental efficiency evaluation analysis.
The aim of the studies was to develop an alternative method which could overcome the lack of sampling to improve the efficiencx of control efforts for bovine endemic fluorosis. The spatial distribution characteristics of the disease were analysed and a prediction model for the estimation of fluorosis distribution in some districts in northwest Liaoning province in China was established. The model used ordinary kriging, and was evaluated using cross-validation. Analysis showed that the distribution of the disease was spatial autocorrelation. The prediction error of the cross-validation (ME = -0.0092, PMSE = 0.627, AKSE = 0.597, and RMSP = 1.007) and comparison with the actual disease distribution indicated that the prediction map accurately distributed bovine endemic fluorosis. It is feasible to predict bovine endemic fluorosis in the area by using ordinary kriging and limited data.
The morphology and ontogeny of the trilobite Changaspis elongata based on 216 specimens collected from the Lazizhai section of the Balang Formation (Stage 4, Series 2 of the Cambrian) in Guizhou Province, South China are described. The relatively continuous ontogenetic series reveals morphological changes, and shows that the species has seventeen thoracic segments in the holaspid period, instead of the sixteen as previously suggested. The development of the pygidial segments shows that their number gradually decreases during ontogeny. A new dataset of well-preserved specimens offers a unique opportunity to investigate developmental traits after segment addition is completed. The ontogenetic size progressions for the lengths of cephalon and trunk show overall compliance with Dyar’s rule. As a result of different average growth rates for the lengths of cephalon, trunk and pygidium, the length of the thorax relative to the body shows a gradually increasing trend; however, the cephalon and pygidium follow the opposite trend. Morphometric analysis across fourteen post-embryonic stages reveals growth gradients with increasing values for each thoracic segment from anterior to posterior. The reconstruction of the development traits shows visualization of the changes in relative growth and segmentation for the different body parts. The new dataset and growth gradient of the trunk suggest that the thoracic segment growth dynamics of early Cambrian to Silurian trilobites follow the same general continuous, steady-state growth gradient decreasing from posterior to anterior.
In this study, the comparative effects of the two disturbances (aquaculture and water level fluctuations) on macroinvertebrate communities were explored in two waterbodies connected with the reservoir system of Three Gorges Reservoir (TGR) in China. One water body called Gaoyang Bay which suffered organic pollution from intensive aquaculture. Another named Hanfeng Lake, where the effects of water-level fluctuations are obvious. The results showed that aquaculture could significantly affect the chemical forms of nutrients, decrease the α-diversity and increase the β-diversity of macroinvertebrates although the communities in the treatment area in Gaoyang Bay were not fundamentally changed comparing to the control area in the same bay. The densities of macroinvertebrates in the treatment area were significantly lower than that of the control area. The composition of functional feeding groups in the treatment area was close to that in Hanfeng Lake, but obviously different from that in the control area in Gaoyang Bay and the collectors and predators dominated the communities in this control area with the highest percentages. Although water-level fluctuations had negative effects on the communities by decreasing the α-diversity and increasing the β-diversity, which were confirmed by the values of Simpson index, Shannon-Wiener index and Harrison's index in the control area of Gaoyang bay and Hanfeng Lake, the adverse effects were relative low compared to aquaculture. In the bays of TGR, the small-scale disturbance (aquaculture activities) had more significant negative effects compared to the big-scale disturbance (water-level fluctuations related to dam operation of TGR).
Plants deploy different strategies to respond and adapt to various stresses. Given that stresses affect plant growth and activity, the responses and tolerance of crops to stresses must be improved through genetic engineering. Inducible promoters, which have vital roles in gene expression and function, are highly desired in biotechnology applications. Thus, novel inducible promoters must be isolated and identified for genetic engineering to improve crop stress responses and tolerance. OsRhoGAPs are involved in plant defense against diverse stresses. In this study, we identified OsRhoGAP2, which is preferentially expressed in rice inflorescences. We isolated the OsRhoGAP2 promoter and analyzed its functions in transgenic Arabidopsis. We fused the GUS reporter with six 5′ deletion fragments (gp1–gp6) of the OsRhoGAP2 promoter with different lengths. Through histochemical analysis, we detected GUS activity in the inflorescences of transgenic Arabidopsis containing gp1, gp3, gp4, and gp5 constructs but not in transgenic Arabidopsis containing gp2 and gp6 constructs. The GUS activity in transgenic plants containing gp1–gp6 constructs changed under different stress treatments. Bioinformatics analysis and experimental results revealed that the core fragment involved in the inflorescence-preferential expression of OsRhoGAP2 and stress responses may be located in the − 706 bp to + 1 bp, or the translated start site, of OsRhoGAP2. Results indicate that OsRhoGAP2 has a conserved role in stress tolerance and exhibits tissue-specific expression patterns in several plant species. This work provides novel insights into the appropriate promoter resources for plant genetic transformation and useful references for biotechnologists to improve stress tolerance in rice.
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