Wyniki wyszukiwania - Biblioteka Nauki

1

Length-frequency compositions and weight-length relations for big-eye tuna, yellowfin tuna, and albacore [Perciformes: Scombrinae] in the Atlantic, Indian, and eastern Pacific Oceans

100%

Zhu G. , Xu L. , Zhou Y. , Dai X.

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nr 2

157-161

EN

Background. Bigeye tuna, Thunnus obesus (Lowe, 1839); yellowfin tuna, Thunnus albacares (Bonnaterre, 1788); and albacore, Thunnus alalunga (Bonnaterre, 1788), are very important species for world fisheries. It is crucial to the future existence of those economically important species that the best possible biological data on the species is provided to fisheries managers. Materials and Methods. The weight–length relations (WLRs) for bigeye tuna, yellowfin tuna, and albacore, collected in the Atlantic, Indian, and eastern Pacific oceans were studied using commonly accepted methodology. Results. Significant differences can be found from the fork length distributions and the WLRs of the above 3 tuna species and the relations of gilled-gutted and whole weight of bigeye and yellowfin tunas collected from the Atlantic, Indian, and Eastern Pacific Oceans. Significant differences of fork length distributions can be found for bigeye tuna, yellowfin tuna, and albacore from the three areas. The growth exponents (b) of bigeye tuna, yellowfin tuna, and albacore collected from the Atlantic, Indian, and eastern Pacific oceans register significant deviations from isometric value of 3. Conclusion. The date collected will be useful for the fisheries management of the three species studied.

2

Study on Adaptive Threshold Segmentation Method Based on Brightness

100%

Zhao D. , Dai X. , Sun G. , Lu T.

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tom R. 88, nr 9b

150-152

EN

Image segmentation is one of the most important steps before the image data analysis, which divided the image into several areas that have strong similarity. With the more and more widely application of the mesh fabric, the quality requirements are more stringent. As the impact of uneven illumination, the image brightness is inconsistent, which bring a great difficulty to the image segmentation of the mesh fabric. In order to eliminate the effect of uneven illumination in the image acquisition of linear CCD camera, the adaptive threshold segmentation method based on brightness is proposed. Compared with the Otsu method, it is better to eliminate the influence of the uneven illumination and provide a good foundation for subsequent data analysis.

PL

Analizowano system segmentacji obrazu polegający na podziale obrazu na obszary o dużym podobieństwie. Przy nierównym naświetleniu powstaje problem segmentacji. Zaproponowano adaptacyjny system progowej segmentacji bazujący na analizie jasności.

3

Estimating the number of components in an OSL decay curve using the Bayesian Information Criterion

88%

Peng J. , Dong Z. , Han F. , Han Y. , Dai X.

Geochronometria

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2014

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tom Vol. 41, no. 4

334--341

EN

The optically stimulated luminescence (OSL) decay curve is assumed to consist of a number of first-order exponential components. Improper estimation of the number of components leads to under-or over-fitting of the curve under consideration. Hence, correct estimation of the number of components is important to accurately analyze an OSL decay curve. In this study, we investigated the possibility of using the Bayesian Information Criterion to estimate the optimal number of components in an OSL decay curve. We tested the reliability of this method using several hundred measured decay curves and three simulation scenarios. Our results demonstrate that the quality of the identification can be influenced by several factors: the measurement time and the number of channels; the variability of the decay constants; and the signal-to-noise ratios of a decaying component. The results also suggest that the Bayesian Information Criterion has great potential to estimate the number of components in an OSL decay curve with a moderate to high signal-to-noise ratio.

4

Variations of cadmium accumulation and translocation in different pakchoi cultivars and screening for Cd-pollution-safe cultivars using cluster analysis

88%

Liu B. , Wu F. , Dai X. , Liu F. , Mi B.

Polish Journal of Environmental Studies

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2019

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tom 28

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nr 4

EN

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.

5

Different Ignition Responses of Powdery and Bulky 1,3,5-Triamino-2,4,6-trinitrobenzene (TATB) Based Polymer-bonded Explosives under Ultra-high Voltage Electrostatic Discharge

63%

Lyu Z. , Long X. , Li Z. , Dai X. , Deng C. , He S. , Li M. , Yao K. , Wen Y.

Central European Journal of Energetic Materials

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2018

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tom Vol. 15, no. 2

283--298

EN

The electric spark induced ignition mechanism for explosives needs further study. The ignition of powdery and bulky TATB by electrostatic discharge (ESD) was investigated. Up to 200 kV ultra-high voltage ESD was applied to powdery and bulky explosives of two TATB-based polymer-bonded explosives (named PBX-1 and PBX-2). The results showed that the spark sensitivities of powdery and bulky explosives are extremely different for the same formulation. The 50% ignition voltages of powdery PBX-1 and PBX-2 were 10.8 kV and 8.5 kV, respectively, while the values for the bulky samples (tablets) were not less than 200 kV. Both heat and the electric field can be transmitted into the powdery samples, on the other hand only the electric field can be transmitted into the bulk samples. The electric field has a smaller contribution while the heat has a larger contribution to the ignition during an ESD, i.e., the thermal effect plays a main role in the ignition process. Our experimental results are in good agreement with recent results calculated by density functional theory.

6

Lycium barbarum polysaccharide protects HSF cells against ultraviolet-induced damage through the activation of Nrf2

63%

Liang B. , Peng L. , Li R. , Li H. , Mo Z. , Dai X. , Jiang N. , Liu Q. , Li Z. , Zhu H.

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tom 23

EN

Background: Lycium barbarum polysaccharide (LBP) is considered an antioxidant agent. NF-E2-related factor-2 (Nrf2) is an important regulator for protection against UV damage. In this study, we verified the performance of LBP and the correlation between LBP and Nrf2. Methods: HSF cells were treated with LBP to determine dose and time dependencies. An antioxidant response element (ARE) reporter was designed to monitor the activity of the Nrf2 antioxidant pathway. Results: For HSF cells, the optimal LBP treatment was 300 μg/ml for 3 h. The AREreporter assay showed that LBP could increase the robustness of p-Nrf2. Treatments with genistein and LY294002 reduced of nuclear p-Nrf2 after 24 h. LBP increased the level of nuclear Nrf2, which functions by both phosphorylation and nuclear translocation. Silencing Nrf2 led to increased reactive oxygen species (ROS) levels, lower cell viability, and decreased superoxide dismutase (SOD) and glutathione peroxidase (GSP-PX) levels. This induced a higher level of lipid peroxide (LPO). However, LBP could decrease the levels of ROS and LPO and enhance the levels of SOD and GSP-PX. Conclusion: LBP protects HSF cells against UV damage via the regulation of Nrf2.

7

Repairing compound-contaminated soil using EK-laccase combination repairing technology

63%

Wang Z. , Ren D. , Dai X. , Kang C. , Zhang S. , Zhang X. , Deng Z. , Huang C. , Guo H.

Polish Journal of Environmental Studies

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2020

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tom 29

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nr 3

8

Compressive optical image encryption using phase-shifting interferometry on a joint transform correlator

63%

Li J. , Jia B. , Dai X. , Lei M. , Yang C. , Li J. , Li H. , Li R.

Optica Applicata

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2017

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tom Vol. 47, nr 2

245--256

EN

A compressive optical image encryption method, which combines compressive sensing with phase-shifting interferometry on a joint transform correlator, is proposed in the fully optical domain. The object image is first permutated using a binary scrambling method. Next, the permutated object field is encrypted and registered as the holograms by phase-shifting interferometry on the joint transform correlator setup. Then, the encrypted images and the key are compressed to the compressed data using single-pixel compressive imaging. The original image can be reconstructed and decrypted using the specified algorithm. The simulations demonstrate that the method is effective and suitable for image security transmission.