Automatic Red-Channel underwater image restoration.

Underwater images typically exhibit color distortion and low contrast as a result of the exponential decay that light suffers as it travels. Moreover, colors associated to different wavelengths have different attenuation rates, being the red wavelength the one that attenuates the fastest. To restore underwater images, we propose a Red Channel method, where colors associated to short wavelengths are recovered, as expected for underwater images, leading to a recovery of the lost contrast. The Red Channel method can be interpreted as a variant of the Dark Channel method used for images degraded by the atmosphere when exposed to haze. Experimental results show that our technique handles gracefully artificially illuminated areas, and achieves a natural color correction and superior or equivalent visibility improvement when compared to other state-of-the-art methods

The Increased Expression of Integrin α6 (ITGA6) Enhances Drug Resistance in EVI1high Leukemia

Ecotropic viral integration site-1 (EVI1) is one of the candidate oncogenes for human acute myeloid leukemia (AML) with chromosomal alterations at 3q26. High EVI1 expression (EVI1high) is a risk factor for AML with poor outcome. Using DNA microarray analysis, we previously identified that integrin α6 (ITGA6) was upregulated over 10-fold in EVI1high leukemia cells. In this study, we determined whether the increased expression of ITGA6 is associated with drug-resistance and increased cell adhesion, resulting in poor prognosis. To this end, we first confirmed the expression pattern of a series of integrin genes using semi-quantitative PCR and fluorescence-activated cell sorter (FACS) analysis and determined the cell adhesion ability in EVI1high leukemia cells. We found that the adhesion ability of EVI1high leukemia cells to laminin increased with the increased expression of ITGA6 and integrin β4 (ITGB4). The introduction of small-hairpin RNA against EVI1 (shEVI1) into EVI1high leukemia cells reduced the cell adhesion ability and downregulated the expression of ITGA6 and ITGB4. In addition, the overexpression of EVI1 in EVI1low leukemia cells enhanced their cell adhesion ability and increased the expression of ITGA6 and ITGB4. In a subsequent experiment, the introduction of shRNA against ITGA6 or ITGB4 into EVI1high AML cells downregulated their cell adhesion ability; however, the EVI1high AML cells transfected with shRNA against ITGA6 could not be maintained in culture. Moreover, treating EVI1high leukemia cells with neutralizing antibodies against ITGA6 or ITGB4 resulted in an enhanced responsiveness to anti-cancer drugs and a reduction of their cell adhesion ability. The expression of ITGA6 is significantly elevated in cells from relapsed and EVI1high AML cases; therefore, ITGA6 might represent an important therapeutic target for both refractory and EVI1high AML

Social Media, Social Capital, and the Civic Participation of College Students

In recent years, social media technology has transformed the ways that Americans interact with each other. Social media usage is particularly high among young adults and college students and recent research suggests that there is a relationship between social media usage and participation in civic and political activities. Recently, research has also examined the relationship between the Internet (and social media) and social capital. The research presented here assesses the extent to which students at a large, public, Midwestern university utilized social media during the 2010 midterm election year, the types of social media they preferred, their levels of social capital, and any impact these factors had on student political and community participation. With the exception of a weak, marginally significant association between Twitter usage and political participation, social media usage does not appear to be directly associated with traditional forms of student civic participation. However, we did find evidence of an indirect, mediated association between students’ social media usage and their civic participation. The importance of the Internet and social media for students appears to lie in its utility as an information gathering tool. Specifically, we found that students who used social media more frequently were more likely to access information about news online, which had a positive impact on levels of civic participation