ut keep evolving as the present knowledge base expands. Part 2 of the special issue on microsaccades is already in progress with articles currently under review and will be published in 2021.The abstract book of the last European Conference on Eye Movements [1] lists abstracts of 373 presentations, but less than five percent investigate vergence eye movements, i.e. the coordination of the right and left eye. Why then a special issue on this neglected issue? Human vision under natural conditions involves both eyes in coordination controlled by interacting processes subsumed under the concept of vergence.. Further, vergence is important for people in their daily lives since disorders of vergence can have serious consequences ophthalmologists deal with squinting patients on the basis of heterophoria and heterotropia testing, eye strain or visual complaints can be related to impaired vergence dynamic or less accurate static vergence, remediation by optometrist includes vergence training or prism eye glasses, etc.Interactive feedback of interface elements and low level of spatial accuracy are two main key points for the interaction research in the Eye-computer interaction system. This study tried to solve these two problems from the perspective of human-computer interactions and ergonomics. Two experiments were conducted to explore the optimum target size and gaze-triggering dwell time of the eye-computer interaction (ECI) system. Experimental Series 1 was used as the pre-experiment to identify the size that has a greater task completion rate. Experimental Series 2 was used as the main experiment to investigate the optimum gaze-triggering dwell time by using a comprehensive evaluation of the task completion rate, reaction time, and NASA-TLX (Task Load Index). In Experimental Series 1, the optimal element size was determined to be 256 × 256p x 2. The conclusion of Experimental Series 2 was that when the dwell time is set to 600 ms, the efficiency of the interface is the highest, and the task load of subjects is minimal as well. Finally, the results of Experiment Series 1 and 2 have positive effects on improving the usability of the interface. The optimal control size and the optimal dwell time obtained from the experiments have certain reference and application value for interface design and software development of the ECI system.Within art literature, there is a centuries-old assumption that the eye follows the lines set out by the composition of a painting. However, recent empirical findings suggest that this may not be true. This study investigates beholders’ saccadic eye movements while looking at fourteen paintings representing the scene of the Last Supper, and their perception of the compositions of those paintings. The experiment included three parts 1) recording the eye movements of the participants looking at the paintings; 2) asking participants to draw the composition of the paintings; and 3) asking them to rate the amount of depth in the paintings. We developed a novel coefficient of similarity in order to quantify 1) the similarity between the saccades of different observers; 2) the similarity between the compositional drawings of different observers; and 3) the similarity between saccades and compositional drawings. Hexa-D-arginine For all of the tested paintings, we found a high, above-chance similarity between the saccades and between the compositional drawings. Additionally, for most of the paintings, we also found a high, above-chance similarity between compositional lines and saccades, both on a collective and on an individual level. Ultimately, our findings suggest that composition does influence visual perception.Microsaccades are involuntary eye movements occurring naturally during fixation. In this study, microsaccades were investigated under monocularly and binocularly stimulated conditions with respect to their directional distribution and rate signature, that refers to a curve reporting the frequency modulation of microsaccades over time. For monocular stimulation the left eye was covered by an infrared filter. In both stimulation conditions, participants fixated a Gabor patch presented randomly in orientation of 45° or 135° over a wide range of spatial frequencies appearing in the center of a monitor. Considering the microsaccadic directions, this study showed microsaccades to be preferably horizontally oriented in their mean direction, regardless of the spatial characteristics of the grating. Furthermore, this outcome was found to be consistent between both stimulation conditions. Moreover, this study found that the microsaccadic rate signature curve correlates between both stimulation conditions, while the curve given for binocular stimulation was already proposed as a tool for estimation of visual performance in the past. Therefore, this study extends the applicability of microsaccades to clinical use, since parameters as contrast sensitivity, has been measured monocularly in the clinical attitude.The emerging pandemic of COVID-19 caused by the novel pathogenic human coronavirus SARS-CoV-2 has caused significant morbidity and mortality across the globe, prompting the scientific world to search for preventive measures to interrupt the disease process. Demographic data indicates gender-based differences in COVID-19 morbidity with better outcome amongst females. Disparity in sex-dependent morbidity and mortality in COVID-19 patients may be attributed to difference in levels of sex steroid hormones -androgens and estrogens. Evidence suggests that apart from the regulation of viral host factors, immunomodulatory and cardioprotective roles exerted by estrogen and progesterone may provide protection to females against COVID-19. Exploring the underlying mechanisms and beneficial effects of these hormones as an adjuvant to existing therapy may be a step towards improving the outcomes. This article aims to review studies demonstrating the role of sex steroidal hormones in modulating SARS-CoV-2 host factors and summarize plausible biological reasons for sex-based differences seen in COVID-19 mortality.Early stage cancer detection technologies can provide functional information and potentially decrease the mortality rate caused by cervical cancer. In our previous work, a miniaturized ultrasound and photoacoustic endoscopic system has been developed to image the cervical tissue through the cervical canal to fulfills the need for a safe, low-cost, and high-resolution functional diagnostic system. However, the miniaturized size of endoscope and American National Standards Institute safety limits cause constraints of using high-intensity illumination during imaging. In addition, the strong light scattering of tissues limits the light penetration depth. Fortunately, the cervix anatomy allows for the delivery of additional light from the ectocervix by using an external illumination system. Here we propose a dual, co-planar illumination system, which can provide adequate illumination to the cervical tissue via combined internal and external light delivery strategies. Therefore, an increase in the area of light-tissue interaction allows us to raise the laser light energy while keeping fluence under safety limits.