A mathematical model for describing the retinal nerve fiber bundle trajectories in the human eye:Average course, variability, and influence of refraction, optic disc size and optic disc position

Previously we developed a mathematical model for describing the retinal nerve fiber bundle trajectories in the superior-temporal and inferior-temporal regions of the human retina, based on traced trajectories extracted from fundus photographs. Aims of the current study were to (i) validate the existing model, (ii) expand the model to the entire retina and (iii) determine the influence of refraction, optic disc size and optic disc position on the trajectories. A new set of fundus photographs was collected comprising 28 eyes of 28 subjects. From these 28 photographs, 625 trajectories were extracted. Trajectories in the temporal region of the retina were compared to the existing model. In this region, 347 of 399 trajectories (87%) were within the 95% central range of the existing model. The model was extended to the nasal region. With this extension, the model can now be applied to the entire retina that corresponds to the visual field as tested with standard automated perimetry (up to approximately 30 eccentricity). There was an asymmetry between the superior and inferior hemifields and a considerable location-specific inter-subject variability. In the nasal region, we found two "singularities", located roughly at the one and five o'clock positions for the right optic disc. Here, trajectories from relatively widespread areas of the retina converge. Associations between individual deviations from the model and refraction, optic disc size and optic disc position were studied with multiple linear regression. Refraction (P = 0.021) and possibly optic disc inclination (P = 0.09) influenced the trajectories in the superior-temporal region. (C) 2012 Elsevier Ltd. All rights reserved

Cross-Cultural Differences in Attitudes Toward Altruism, Forgiveness and Gratitude

Cross-Cultural Differences in Attitudes Toward Altruism, Forgiveness and Gratitude As a relatively new field of study, positive psychology has rarely been assessed in a cross-cultural context. The present study aimed to compare Chinese, Taiwanese and American cultures in regards to five central aspects of positive psychology: altruism, forgiveness, gratitude, life satisfaction (SWL), and psychological well-being (PWB). Additionally, culture-based perceptions and stereotypes concerning these positive psychological principles were also addressed. A 67-item survey was administered undergraduate students from universities in both China (n=139) and Taiwan (n=112), and will be administered to undergraduate students at SUNY Fredonia. The survey consisted of items from the Heartland Forgiveness Scale, the GQ-6 questionnaire, the Helping Attitudes Scale, Ryff’s PWB, and the SWLS. Half of the participants in each sample answered as themselves and, to address potential stereotypes, the other half answered as they would if they were hypothetically a member of the other culture (e.g. a Chinese participant would answer as if they were an American). Chinese participants who answered for themselves (CS) had significantly higher scores on forgiveness than Chinese participants who answered as if they were Americans (CA). However, CA participants had significantly higher scores than CS participants on the PWB subscales of personal growth and self-acceptance. Taiwanese participants answering as themselves (TS) scored significantly higher in gratitude than Taiwanese students who answered as Americans (TA). Additionally, significant correlations were found in each of the samples between several of the major positive psychological facets. Because this study is still in progress, data from the American sample has yet to be collected. However, preliminary results indicate important differences between the eastern cultures’ perceptions of themselves and their perceptions of Americans. We believe that additional findings will further our understanding of the influence of cultures on attitudes and perceptions. Keywords: Altruism, Forgiveness, Gratitude, Life Satisfaction, Psychological Well-being, Cultur

Information Reference Models for European Pork Supply Networks – Identifying Gaps in Information Infrastructures –

 Several global developments such as diminishing production resources, limits in the availability of water and the growing demand for bio-energy as well as sector-wide crises (e.g. BSE, swine fever, dioxin) have led to a changing attitude of society towards the conse-quences of the food system‘s activities for social, economic and environmental issues, cap-tured in the term of sustainability. As a consequence, consumers show increasing interest in the characteristics of food, and in turn, on the availability of related information and guaran-tees. The paper introduces different information reference models for European pork supply networks, which give an aggregated overview about information availability and exchange in the pork sector, identify additional information demands of decision makers at different stages of pork production, and identify gaps in the existing information infrastructure. The models support different parties involved in pork production, such as enterprises, system developers and consultants, in developing enterprise or network specific solutions

Proglacial erosion rates and processes in a glacierized catchment in the Swiss Alps

In the Swiss Alps, climatic changes have not only caused glacier retreat, but also likely increased sedimentation downstream of glaciers. This material either originates from below the glacier or from periglacial environments, which are exposed as glaciers retreat, and often consist of easily erodible sediment. Griesgletscher's catchment in the Swiss Alps was examined to quantify erosion in the proglacial area, possible hydrological drivers and contributions of the sub- and periglacial sources. Digital elevation models, created from annual aerial photographs, were subtracted to determine annual volume changes in the proglacial area from 1986 to 2014. These data show a strong increase in proglacial erosion in the decade prior to 2012, coincident with increasing proglacial area size. However, examination of the gradient between discharge and sediment evacuation, and modeled sediment transport, could suggest that the proglacial area began to stabilize and sediment supply is limited. The large influx of sediment into the proglacial reservoir, which is roughly 2.5 times greater than the amount of sediment eroded from the proglacial area, demonstrates the importance of subglacial erosion to the catchment's sediment budget. Although far more sediment originates subglacially, erosion rates in the proglacial area are over 50 times greater than the rest of the catchment. In turn, both sub- and periglacial processes, in addition to constraining sediment supply, must be considered for assessing future sediment dynamics as glacier area shrinks and proglacial areas grow

Influence of the Retinal Blood Vessel Topography on the Variability of the Retinal Nerve Fiber Bundle Trajectories in the Human Retina

PURPOSE. To determine the relationship between the retinal blood vessel topography and the retinal nerve fiber bundle (RNFB) trajectories in the human retina. METHODS. A previously collected dataset comprising 28 fundus photographs with traced RNFB trajectories was used. For all traced trajectories, the departure from our previously published RNFB trajectory model was calculated. Subsequently, we calculated, per subject, a "mean departure" for the superior-temporal and inferior-temporal region. We measured angles between a line connecting the optic nerve head (ONH) center and the fovea and lines connecting the ONH center and the crossings of the superior and inferior temporal arteries (arterial angles) and veins (venous angles) with circles around the ONH; circle radii were 25%, 50%, and 100% of the ONH center-to-fovea distance. We also defined two angles based on the location of the first arteriovenous crossing. Multiple linear regression analysis was performed with mean departure as dependent variable and refraction, ONH inclination, and vessel angles as independent variables. RESULTS. In the superior-temporal region, refraction (P = 0.017), ONH inclination (P = 0.021), and the arterial angle corresponding to the middle circle (P <0.001) were significant determinants of mean departure. Explained variance was 0.54. In the inferior-temporal region, the arterial angle corresponding to the largest circle (P = 0.002) was significant. Explained variance was 0.32. CONCLUSIONS. The retinal blood vessel topography explains a significant part of the RNFB trajectory variability but only if (1) the vessel topography is assessed at an appropriate distance from the ONH and (2) the superior and inferior hemifield are addressed independently