Feature Extraction and Matching of Humanoid-Eye Binocular Images Based on SUSAN-SIFT Algorithm.

Imitating the visual characteristics of human eyes is one of the important tasks of digital image processing and computer vision. Feature correspondence of humanoid-eye binocular images is a prerequisite for obtaining the fused image. Human eyes are more sensitive to edge, because it contains much information. However, existing matching methods usually fail in producing enough edge corresponding pairs for humanoid-eye images because of viewpoint and view direction differences. To this end, we propose a novel and effective feature matching algorithm based on edge points. The proposed method consists of four steps. First, the SUSAN operator is employed to detect features, for its outstanding edge feature extraction capability. Second, the input image is constructed into a multi-scale structure based on image pyramid theory, which is then used to compute simplified SIFT descriptors for all feature points. Third, a novel multi-scale descriptor is constructed, by stitching the simplified SIFT descriptor of each layer. Finally, the similarity of multi-scale descriptors is measured by bidirectional matching, and the obtained preliminary matches are refined by subsequent procedures, to achieve accurate matching results. We respectively conduct qualitative and quantitative experiments, which demonstrate that our method can robustly match feature points in humanoid-eye binocular image pairs, and achieve favorable performance under illumination changes compared to the state-of-the-art.

Multivalent sialic acid materials for biomedical applications.

Sialic acid is a kind of monosaccharide expressed on the non-reducing end of glycoproteins or glycolipids. It acts as a signal molecule combining with its natural receptors such as selectins and siglecs (sialic acid-binding immunoglobulin-like lectins) in intercellular interactions like immunological surveillance and leukocyte infiltration. The last few decades have witnessed the exploration of the roles that sialic acid plays in different physiological and pathological processes and the use of sialic acid-modified materials as therapeutics for related diseases like immune dysregulation and virus infection. In this review, we will briefly introduce the biomedical function of sialic acids in organisms and the utilization of multivalent sialic acid materials for targeted drug delivery as well as therapeutic applications including anti-inflammation and anti-virus.

Simulated warming enhances biological invasion of Solidago canadensis and Bidens frondosa by increasing reproductive investment and altering flowering phenology pattern.

Phenological and reproductive shifts of plants due to climate change may have important influences on population dynamics. Climate change may also affect invasive species by changing their phenology and reproduction, but few studies have explored this possibility. Here, we investigated the impact of climate change on the phenology, reproduction and invasion potential of two alien Solidago canadensis and Bidens frondosa and one native weed, Pterocypsela laciniata, all of which are in the Asteraceae family. The three species responded to simulated climate change by increasing reproductive investments and root/leaf ratio, prolonging flowering duration, and while the two alien species also displayed a mass-flowering pattern. Moreover, our experimental results indicated that the alien invasive species may have greater phenological plasticity in response to simulated warming than that of the native species (P. laciniata). As such, climate change may enhance the invasion and accelerate the invasive process of these alien plant species.

Simulated warming shifts the flowering phenology and sexual reproduction of Cardamine hirsuta under different Planting densities.

Climate warming can shift the reproductive phenology of plant, and hence dramatically reduced the reproductive capacity both of density-dependent and -independent plant species. But it is still unclear how climate warming affects flowering phenology and reproductive allocation of plant under different planting densities. Here, we assessed the impact of simulated warming on flowering phenology and sexual reproduction in the ephemeral herb Cardamine hirsuta under four densities. We found that simulated warming delayed the onset of flowering averagely for 3.6 days but preceded the end of flowering for about 1 day, which indicated climate warming shortened the duration of the flowering. And the flowering amplitude in the peak flowering day also dramatically increased in the simulated warming treatment, which caused a mass-flowering pattern. Climate warming significantly increased the weights of the fruits, seeds and seed, but reduced fruit length and sexual reproductive allocation under all the four densities. The duration of flowering was shortened and the weights of the fruits, seeds and seed, and sexual reproductive allocation were reduced under The highest density.

[Effects of organic acids on Cd desorption of South China red soil].

Cadmium (Cd) pollution greatly threatens the environment of South China, where the economy developed very fast during last 20 years. In this paper, batch experiments were conducted to study the effects of three organic acids and their mixed solutions on the Cd desorption of red soil in this region. The results showed that oxalic acid and malic acid retarded the Cd desorption, but oxalic acid promoted it when the concentration was 20 mmol x L(-1) and soil pH value was higher than 5.0. With the increase of soil pH, Cd desorption decreased rapidly in the presence of oxalic acid and malic acid. Citric acid retarded Cd desorption at pH < 5.0, but promoted it at pH > 5.0. When the concentration of citric acid was 2 mmol x L(-1) and pH value changed from 3.0 to 7.0, Cd desorption declined first, increased then, and declined again. But, at the citric acid concentration of 20 mmol x L(-1), Cd desorption declined first till pH 4.0, and increased then till pH 7.0. At low pH (3.0 and 4.0), malic acid desorbed most Cd; while at high pH (5.0-7.0), citric acid desorbed most Cd. The Cd desorption rate was much higher in the presence of citric acid than oxalic acid and malic acid. Organic acids did not interactive effect on Cd desorption. The Cd desorption rate by mixed acids was within the range of that by single acid alone.