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There is no doubt at all that the power of perspective depends on the nature of the angles, and that the appearance of things changes when the centre and the eye change, and that it is not sufficient for the erudite and expert to see and consider the bare lineaments of bodies and shapes put into perspective in order to judge things.

The aim was to ascertain whether the characteristics of the corneal pulse (CP) measured in-vivo in a rabbit eye change after short-term artificial increase of intraocular pressure (IOP) and whether they correlate with corneal biomechanics assessed in-vitro. Eight New Zealand white rabbits were included in this study and were anesthetized. In-vivo experiments included simultaneous measurements of the CP signal, registered with a non-contact method, IOP, intra-arterial blood pressure, and blood pulse (BPL), at the baseline and short-term elevated IOP. Afterwards, thickness of post-mortem corneas was determined and then uniaxial tensile tests were conducted leading to estimates of their Young's modulus ( E ). At the baseline IOP, backward stepwise regression analyses were performed in which successively the ocular biomechanical, biometric and cardiovascular predictors were separately taken into account. Results of the analysis revealed that the 3rd CP harmonic can be statistically significantly predicted by E and central corneal thickness (Models: R 2 = 0.662, p 0.005 and R 2 = 0.832, p R 2 = 0.534, p = 0.015 and R 2 = 0.509, p

This experiment aims at validating the percentage of visible white in the eye as an emotional indicator, related to the frustration–contentedness axis, in cattle. Earlier experiments showed that the calculated percentage of white in the eyes was larger in frustrated or scared cows compared to cows that were offered a positive stimulus. This eye change was therefore suggested to be a dynamic indicator of emotions in dairy cattle, a high percentage of white in the eye indicating frustration, and a low percentage indicating satisfaction. In the present paper, the hypothesis was that treatment with the anti-anxiety drug diazepam should reduce the percentage of white in the eye in frustrated cows, but have no effect on the percentage of eye white in non-frustrated or rewarded cows. The test animals were 20 randomly selected commercial dairy cows (Norwegian Red Cattle). Two experiments were performed on hungry cows. The four different groups in the first experiment are described in the following. Ten cows were introduced to a frustrating situation, being thwarted from access to visible food (treatment I). Ten cows were introduced to a positive situation, access to food (treatment II). The 10 cows in group I were introduced to the same frustrating situation, but were now pretreated with diazepam (treatment III). The 10 cows in group II were introduced to the same positive situation after pretreatment with diazepam (treatment IV). The two groups in the second experiment were 20 untreated (treatment I) and 20 diazepam-treated (treatment II) cows introduced to a positive, conditioned stimulus, a stockman entering the stall at concentrate feeding time. All predictions were confirmed, supporting the hypothesis that increased percentage of eye white is an emotional indicator of frustration in cows.

Purpose To use optical coherence tomography (OCT) to test the hypothesis that optic nerve head (ONH) “cupping” in the monkey optic nerve transection (ONT) model does not include posterior laminar deformation. Methods Five monkeys (aged 5.5–7.8 years) underwent ONH and retinal nerve fiber layer (RNFL) OCT imaging five times at baseline and biweekly following unilateral ONT until euthanization at ∼40% RNFL loss. Retinal nerve fiber layer thickness (RNFLT) and minimum rim width (MRW) were calculated from each pre- and post-ONT imaging session. The anterior lamina cribrosa surface (ALCS) was delineated within baseline and pre-euthanasia data sets. Significant ONT versus control eye pre-euthanasia change in prelaminar tissue thickness (PLTT), MRW, RNFLT, and ALCS depth (ALCSD) was determined using a linear mixed-effects model. Eye-specific change in each parameter exceeded the 95% confidence interval constructed from baseline measurements. Results Animals were euthanized 49 to 51 days post ONT. Overall ONT eye change from baseline was significant for MRW (−26.2%, P = 0.0011), RNFLT (−43.8%, P < 0.0001), PLTT (−23.8%, P = 0.0013), and ALCSD (−20.8%, P = 0.033). All five ONT eyes demonstrated significant eye-specific decreases in MRW (−23.7% to −31.8%) and RNFLT (−39.6% to −49.7%). Four ONT eyes showed significant PLTT thinning (−23.0% to −28.2%). The ALCS was anteriorly displaced in three of the ONT eyes (−25.7% to −39.2%). No ONT eye demonstrated posterior laminar displacement. Conclusions Seven weeks following surgical ONT in the monkey eye, ONH cupping involves prelaminar and rim tissue thinning without posterior deformation of the lamina cribrosa.