“Titanium dioxide (TiO 2 ) is a semiconductor material that exhibits antibacterial activity due to its photocatalytic properties under ultraviolet light. On the other hand, silver also exhibits strong antibacterial activity towards a wide range of microorganisms and TiO 2 with silver addition exhibits more efficient photocatalytic properties than unmodified TiO 2 . In this work, TiO 2 nanoparticles were synthesized by the hydrothermal method and modified with silver by two different methods: wet impregnation ( Ex situ ) and In situ incorporation. The antimicrobial activity of TiO 2 nanoparticles synthesized and modified by both methods was evaluated against Escherichia coli and Staphylococcus aureus . The results showed that TiO 2 nanoparticles have anatase phase. Also, spherical morphology with a mean particle size around 10.6 nm was obtained. The presence of silver in the modified TiO 2 nanoparticles was confirmed by EDS and XPS. TiO 2 particles modified by the Ex situ method, showed a better bactericidal activity compared to the particles modified by In situ incorporation method and TiO 2 unmodified nanoparticles. This study demonstrated that both methods used to modify the titanium dioxide nanoparticles are effective as bactericidal materials and better results were found for the Ex situ method.”

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In vitro wound healing assay is a useful method to assess cell proliferation and migration, in this context quantification of the process is a critical step. Objective: to develop an automatic segmentation method for wound healing image analysis. Methods: sixty sequential images of two liver tumorderived cell lines were acquired and processed with a region growing-based segmentation algorithm performed in MATLAB. Results: after image processing HepG2 cells presented a low migration rate respect to SkHep1. Although there were visual differences during evaluation of automatic methodology with a manual segmentation carried out under the supervision of an expert, the average differences determined as percentage of wound region (%WR) in image segmentation were just of 0.97% (n=44) for HepG2 and 0.32% (n=16) in SkHep1. Conclusion: this novel approach is a simple alternative to quantify wound healing assay on sequential images.

Ornamental floriculture is one of the main economic activities in different regions of Colombia. Different flowers have a great success, but its industry faces some challenges on phytosanitary controls caused mainly by the dependence on human monitors and the expertise in the detection of diseases throughout the crop fields. This paper focuses on the detection of the affection patterns caused by tomato spotted wilt virus, puncture leaf miner, and leaf miner larvae on chrysanthemum flowers (Dendrathema grandiflorum). A spectral imaging system was with 11 spectral channels was implemented which were generated by the same number of light emitting diodes groups. By using these images, there were carried out different image processing techniques and the combination of different linear relations among the spectral images were tested to enhance, isolate and quantify the affected area on the leaves. The results show that our system has more selective spectral width than common artificial vision systems and the effects of the diseases can be effectively detected.