Human Performance Modeling For Two-Dimensional Dwell-Based Eye Pointing

Recently, Zhang et al. (2010) proposed an effective performance model for dwell-based eye pointing. However, their model was based on a specific circular target condition, without the ability to predict the performance of acquiring conventional rectangular targets. Thus, the applicability of such a model is limited. In this paper, we extend their one-dimensional model to two-dimensional (2D) target conditions. Carrying out two experiments, we have evaluated the abilities of different model candidates to find out the most appropriate one. The new index of difficulty we redefine for 2D eye pointing (IDeye) can properly reflect the asymmetrical impact of target width and height, which the later exceeds the former, and consequently the IDeyemodel can accurately predict the performance for 2D targets. Importantly, we also find that this asymmetry still holds for varying movement directions. According to the results of our study, we provide useful implications and recommendations for gaze-based interactions

Mutations that promote furin-independent growth of Semliki Forest virus affect p62–E1 interactions and membrane fusion

AbstractThe enveloped alphavirus Semliki Forest virus (SFV) infects cells via a low pH-triggered membrane fusion reaction mediated by the E1 protein. E1's fusion activity is regulated by its heterodimeric interaction with a companion membrane protein E2. Mature E2 protein is generated by furin processing of the precursor p62. Processing destabilizes the heterodimer, allowing dissociation at acidic pH, E1 conformational changes, and membrane fusion. We used a furin-deficient cell line, FD11, to select for SFV mutants that show increased growth in the absence of p62 processing. We isolated and characterized 7 such pci mutants (p62 cleavage independent), which retained the parental furin cleavage site but showed significant increases in their ability to carry out membrane fusion in the p62 form. Sequence analysis of the pci mutants identified mutations primarily on the E2 protein, and suggested sites important in the interaction of p62 with E1 and the regulation of fusion

Evaluation of a Drought Tolerance Native Grass: \u3cem\u3eCleistogenes songorica\u3c/em\u3e for the Turf Use Purpose

Water deficit is one of the most important factors to restrict growth of turf grass, especially in northwest China where water available for landscape irrigation is increasingly limited. Use of drought-tolerant turfgrass species or cultivars is one of the strategies used to reduce water utilization and irrigation requirement (Nielsen and Stewart 1990). Recent study showed that regionally adapted native grass species are worth investigating as suitable alternatives to the conventional turfgrasses in many applications (Mark et al. 2011), and several native grass species are suitable for low-maintenance turfgrass use has also been reported (Mintenko et al. 2002). Awnless cleistogenes (Cleistogenes songorica) is a drought tolerance perennial grass native to the northwest desert grasslands of China. It grows well with a mean annual rainfall of 100 to 200 mm and is tolerant to the winter temperatures as low as -40oC. A series of studies related to the domestication of this species have been reported by the writers including seed germination ecology (Yu et al. 2004), seedling establishment techniques (Tai et al. 2008) and seed production (Wei 2010). This paper reports the performance of C. songorica as a turf use grass under drought conditions

The Influence of Social Support on College Students’ Work Volition: The Mediating Effect Based on Self-efficacy

Taking the General Self-efficacy Scale, Perceived Social Support Scale and Work Volition Scale for College Students as the measuring tools, 338 college students were enrolled in the current study to assess the predictors of Work Volition among this population. The results indicated that (a) self-efficacy had a significantly direct impact on work volition, and (b) self-efficacy served as a mediating role between social support and self-efficacy. To promote work volition among college students during their career-seeking activities, it was suggested that increasing their social support so as to develop students’ self-efficacy was of utmost importance. Specific recommendations, limitations and future directions were also discussed in this research