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1

Passive localization for mixed-field moving sources

100%
Gao C., Liu H.
Polish Maritime Research
|
2018
|
tom 25
|
nr Special Issue S2
Due to the mobility of underwater equipment, high-precision underwater positioning technology will face two technical challenges: dealing with mixed-field signals composed of near-field signals and far-field signals; adapting to variable component of mixed-field signals considering the mobility of equipment. Under this condition, an effective method based on MUSIC is addressed in this paper. After distinguishing far-field signal subspace from mixed-field signal subspace, estimations of DOAs and powers of far-field sources are carried out. Then the corresponding far-field and noise signal components can be eliminated from the signal subspace. After that, based on path-following algorithm, modified 2D-MUSIC is performed for DOA and range estimations of near-field sources. The performance of the proposed method is verified and compared with the other methods through computer simulations. Reasonable classification of source types and accurate localization estimation can be achieved by using the proposed method
2
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Anatomy of the Early Cretaceous enantiornithine bird Rapaxavis pani

81%
O'Connor J. K., Chiappe L. M., Gao C., Zhao B.
Acta Palaeontologica Polonica
|
2011
|
tom 56
|
nr 3
The exquisitely preserved longipterygid enantiornithine Rapaxavis pani is redescribed here after more extensive preparation. A complete review of its morphology is presented based on information gathered before and after preparation. Among other features, Rapaxavis pani is characterized by having an elongate rostrum (close to 60% of the skull length), rostrally restricted dentition, and schizorhinal external nares. Yet, the most puzzling feature of this bird is the presence of a pair of pectoral bones (here termed paracoracoidal ossifications) that, with the exception of the enantiornithine Concornis lacustris, are unknown within Aves. Particularly notable is the presence of a distal tarsal cap, formed by the fusion of distal tarsal elements, a feature that is controversial in non−ornithuromorph birds. The holotype and only known specimen of Rapaxavis pani thus reveals important information for better understanding the anatomy and phylogenetic relationships of longipterygids, in particular, as well as basal birds as a whole.
3

Bindarit attenuates pain and cancer-related inflammation by influencing myeloid cells in a model of bone cancer

71%
Liu S., Gao H., Gao C., Liu W., Xing D.
Archivum Immunologiae et Therapiae Experimentalis
|
2018
|
tom 66
|
nr 3
4

Research on runoff pollution characteristics and countermeasures at sensitive highway sites

71%
Wang Y., Gao C., Yang S., Ji G., Liu X.
Polish Journal of Environmental Studies
|
2016
|
tom 25
|
nr 2
Pollution and control on highway surface runoff have become a serious problem in highway environmental protection. Constructing a highway in a water conservation district could bring benefi ts as well as a variety of environmental pollution and potential damage. Based on water conservation district sensitivity and highway runoff characteristics, the current paper analyzes the impact of highway runoff on water quality in the water source protection area. It hasn’t yet had a good and mature process with respect to the drainage of the drinking water source reserves of domestic highways. It was designed as a concentrated drainage treatment system to process the drainage of sensitive sections as outlined in this paper. Highway surface runoff characteristics were studied by monitoring, investigating, sampling, and analyzing the Renhuai-to- Chishui highway (RCH), and then the concentrated drainage treatment system was designed, and the water is collected piecewise along the route. The processing system can not only effectively deal with road surface runoff of the water source protection area, but also to cope with risk. Combined with the actual situation of water source conservation areas around RCH, we have carried out a detailed demonstration of the drainage system in order to mollify the contradiction between the water resource protection area and development of traffi c in the water reserves. The results showed that the processing rates – as high as 83.17-93.77% – and the concentrated drainage treatment system could guarantee effl uents meeting discharge standards. This study demonstrates the effectiveness of the concentrated drainage treatment system in RCH and establishes an advanced technology for highway surface runoff control.
5

Experimental study of herbaceous structure effects on reducing nutrient loss

61%
Gao C., Cheng J., Li F., Zhang H., Yang F., Dai J.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 3
The objective of this study was to evaluate nutrient loss under herbaceous cover in simulated field conditions and quantify the influences of the aerial and underground parts of plants in preventing nutrient loss. The experimental settings were as follows: two herbs, i.e., alfalfa (Medicago sativa L.) and green foxtail (Setariaviridis (L.) Beauv.); four covers for each herb (0, 20-30%, 50-60%, and 80-90%); and two treatments (reserving the entire plant and trimming the aerial part of the plant). Through simulated rainfall, runoff and sediment samples were collected at the end of the soil tank and analysed for nitrogen (N) and phosphorus (P). The results indicated that nutrient loss gradually decreased with the increasing plant coverage, and the nutrient loss on the green foxtail slope was lower than that on the alfalfa slope under the same coverage. Although the effect of the alfalfa canopy on nutrient loss prevention was higher than that of the green foxtail, the capacity of the green foxtail root for conserving nutrients is stronger than that of alfalfa due to a different herbaceous plant leaf area index and root morphology distribution. An exponential function was found to characterize the different plant root length densities and nutrient losses on the slope.
6

Expression of factors involved in the regulation of angiogenesis in the full-term human placenta: effects of in vitro fertilization

51%
Li C., Zhang Y., Tang L., Zhao H., Gao C., Gao L., Cui Y., Liu J.
Reproductive Biology
|
2016
|
tom 16
|
nr 2
7

Effects of Abietinella abietina extracts on the germination and seedling emergence of Picea crassifolia: results of greenhouse experiments

42%
Wang Q., Zhao C., Gao Y., Gao C., Qiao Y., Xie H., Wang W., Yuan L., Liu J., Ma W., Li W.
Polish Journal of Ecology
|
2016
|
tom 64
|
nr 3
Moss cushion plays an important role in recruitment of vascular plants. In this study, we examined the effects of water soluble extracts (WSE) of Abietinella abietina on germination of Qinghai spruce (Picea crassifolia) and the effects of moss substrates (A. abietina) on seedling emergence of P. crassifolia in two greenhouse experiments. We found that the WSE of moss affected germination of P. crassifolia in two ways: (1) the WSE reducing the risk of fungal infection to the seeds, improve the germination rate; and (2) the WSE affects germination by its concentration, that is, low concentrations of WSE (i.e., 0.5 mg ml⁻¹ and 5 mg ml⁻¹) stimulate, while high concentrations (i.e., 50 mg ml⁻¹) inhibit it. In seedling emergence experiments, we detected that the moss substrates (both thick and thin mosses) facilitate the emergence of P. crassifolia in dry and intermediate moisture conditions, but inhibit it in moist conditions. In bare soil, the P. crassifolia emergence was also controlled by moisture conditions; the highest (60%) and the lowest (35%) emergence occurred in the moist conditions and dry conditions, respectively. We also found that P. crassifolia seedlings were thinner and taller, but their number higher in moss cushion than in bare soil. Thus we conclude that there is nurse effect of A. abietina cushion on recruitment of P. crassifolia in both dry and intermediate moisture conditions.
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