A note on larger orbit size

In this note, we present an improvement on the large orbit result of Halasi and Podoski, and then answer an open question raised in [X. Chen, J. P. Cossey, M. Lewis and H. P. Tong-Viet, Blocks of small defect in alternating groups and squares of Brauer character degrees, J. Group Theory 20 2017, 6, 1155–1173].

Computational Characterization of the Dish-In-A-Dish, A High Yield Culture Platform for Endothelial Shear Stress Studies on the Orbital Shaker

Endothelial cells sense and respond to shear stress. Different in vitro model systems have been used to study the cellular responses to shear stress, but these platforms do not allow studies on high numbers of cells under uniform and controllable shear stress. The annular dish, or dish-in-a-dish (DiaD), on the orbital shaker has been proposed as an accessible system to overcome these challenges. However, the influence of the DiaD design and the experimental parameters on the shear stress patterns is not known. In this study, we characterize different designs and experimental parameters (orbit size, speed and fluid height) using computational fluid dynamics. We optimize the DiaD for an atheroprotective flow, combining high shear stress levels with a low oscillatory shear index (OSI). We find that orbit size determines the DiaD design and parameters. The shear stress levels increase with increasing rotational speed and fluid height. Based on our optimization, we experimentally compare the 134/56 DiaD with regular dishes for cellular alignment and KLF2, eNOS, CDH2 and MCP1 expression. The calculated OSI has a strong impact on alignment and gene expression, emphasizing the importance of characterizing shear profiles in orbital setups.

Analysis of M/G/1 retrial queues with second optional service and customer balking under two types of Bernoulli vacation schedule

An M/G/1 retrial queueing system with two phases of service of which the second phase is optional and the server operating under Bernoulli vacation schedule is investigated. Further, the customer is allowed to balk upon arrival if he finds the server unavailable to serve his request immediately. The joint generating functions of orbit size and server status are derived using supplementary variable technique. Some important performance measures like the orbit size, the system size, the server utilisation and the probability that the system is empty are found. Stochastic decomposition law is established when there is no balking permitted. Some existing results are derived as special cases of our model under study. Interestingly, these performance measures are compared for various vacation schedules namely exhaustive service, 1-limited service, Bernoulli vacation and modified Bernoulli vacation schedules. Extensive numerical analysis is carried out to exhibit the effect of the system parameters on the performance measures.

The relationship between latitudinal light variation and orbit and cranial size in humans

Increased orbit size is suggested to be an adaptation for enhanced visual acuity and sensitivity in conditions of reduced light quality. Whilst light ambience has a well established correlation with eye size in birds and primates, evidence in humans is very limited. The aim of this study was to analyse the anatomical compensations of the eye and visual cortex as a result of varying levels of light exposure. It was hypothesized that humans of higher latitudes will have an increased orbit size to improve visual sensitivity and acuity in conditions of decreased light, and thus greater cranium size due to enlarged visual cortices. Craniometric measurements of 1,209 male and 1,021 female individuals from 27 series coming from different latitudes were sourced from William W. Howells Craniometric Data Set. Mean cranial and orbit size was calculated by combining linear craniometric measurements of length, width and height for individual males and females at each latitude. Linear regressions of orbit and cranial size on latitude were created and significance was measured using Pearson’s r and P value. Partial correlations were calculated to test whether orbit size correlates with latitude independent of cranial size. Significant positive correlations were found between i) orbit and cranial size and ii) orbit size and latitude and iii) cranial size and latitude in males and females. Additionally, partial correlation values for latitude and orbit size were significant in both males and females. The relationship between visual system size and increasing latitude among humans is currently understudied. Significant relationships between visual system size and increasing latitude suggest that enlarged eyes were an evolutionary mechanism for individuals with compromised light availability. Other factors related to varying geographic location may also play a role

Variations in Eyeball Diameters of the Healthy Adults

Thepurposeof the current research was to reevaluate the normative data on the eyeball diameters.Methods. In a prospective cohort study, the CT data of consecutive 250 adults with healthy eyes were collected and analyzed, and sagittal, transverse, and axial diameters of both eyeballs were measured. The data obtained from the left eye and from the right eye were compared. The correlation analysis was performed with the following variables: orbit size, gender, age, and ethnic background.Results. We did not find statistically significant differences correlated with gender of the patients and their age. The right eyeball was slightly smaller than the left one but this difference was statistically insignificant(P=0.17). We did not find statistically significant differences of the eyeball sizes among the ethnicities we dealt with. Strong correlation was found between the transverse diameter and the width of the orbit(r=0.88).Conclusion. The size of a human adult eye is approximately24.2 mm (transverse) × 23.7 mm (sagittal) × 22.0–24.8 mm(axial) with no significant difference between sexes and age groups. In the transverse diameter, the eyeball size may vary from 21 mm to 27 mm. These data might be useful in ophthalmological, oculoplastic, and neurological practice.