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An accurate solid eye model (with volumetric retinal morphology) has many applications in the field of ophthalmology, including evaluation of ophthalmic instruments and optometry/ophthalmology training. We present a method that uses volumetric OCT retinal data sets to produce an anatomically correct representation of three-dimensional (3D) retinal layers. This information is exported to a laser scan system to re-create it within solid eye retinal morphology of the eye used in OCT testing. The solid optical model eye is constructed from PMMA acrylic, with equivalent optical power to that of the human eye (∼58D). Additionally we tested a water bath eye model from Eyetech Ltd. with a customized retina consisting of five layers of ∼60 μm thick biaxial polypropylene film and hot melt rubber adhesive. © 2010 SPIE.

This paper describes the design and accuracy evaluation of a dynamometric pedal, which measures the two pedal force components in the plane of the bicycle. To realize a design that could be used during actual off-road cycling, a popular clipless pedal available commercially was modified so that both the form and the function of the original design were maintained. To measure the load components of interest, the pedal spindle was replaced with a spindle fixed to the pedal body and instrumented with eight strain gages connected into two Wheatstone bridge circuits. The new spindle is supported by bearings in the crank arm. Static calibration and a subsequent accuracy check revealed root mean square errors of less than 1 percent full scale (FS) when only the force components of interest were applied. Application of unmeasured load components created an error less than 2 percent FS. The natural frequency with half the weight of a 75 kgf person standing on the pedal was greater than 135 Hz. These performance capabilities make the dynamometer suitable for measuring either pedaling loads due to the rider's muscular action or inertial loads due to surface-induced acceleration. To demonstrate this suitability, sample pedal load data are presented both for steady-state ergometer cycling and coasting over a rough surface while standing.

The skeleton of the sharks, rays, and chimaeroids is composed of cartilage, some of which is calcified. The vertebrae are completely calcified, while the remainder of the skeleton has one or more thin layers of calcified blocks (tesserae) covering a core of uncalcified cartilage. In a clade of stingrays containing hard prey specialists an internal network of calcified struts augments the surface calcification. This strut-reinforced tissue is called trabecular cartilage. Some sharks, most notably the heterodontids, also eat hard prey. We examined a size series of Heterodontus francisci with a high resolution CT scanner for evidence of trabecular cartilage and to examine the morphology of the jaw joint. The CT scans and dissection revealed no trace of trabeculae. The jaw mechanism is the mechanical antithesis of that of the hard prey crushing stingrays. The rays have a well-calcified symphysis but the upper and lower jaws meet at a joint that has a large uncalcified region. In contrast heterodontids have an extremely loose, uncalcified, ligamentous symphysis and the upper and lower jaw joints form a well-calcified hinge joint. This raises the possibility that the left and right side of the shark's jaws work as levers with the fulcrum at the joint. Dissection of other shark taxa that are reported to eat hard prey, Sphyrna tiburo and Orectolobus omatus, did not reveal any trabecular cartilage. Trabecular cartilage appears to be an evolutionary innovation, confined to the myliobatid stingrays that allows them to eat harder prey than other cartilaginous fishes.

Nearly all mammals possess a complex bony scroll, the maxilloturbinals, within the nasal chamber that functions to conserve water and warm inspired air during ventilation. Although maxilloturbinal structure differs greatly among species, the functional significance of this variation is not understood. In part, this is because the fine-scale and internal location of turbinals makes them difficult to visualize. Hi-resolution CT scan technology can now resolve these delicate bones and so allows the first quantitative analysis of turbinal structure. Here we report the results of a comparison of maxilloturbinals in two canids, the wild dog (Lycaon pictus) and the bush dog (Speothos venaticus), two species that differ greatly in locomotor abilities (long distance pursuit vs. short distance rush) and environment (arid savannah vs. mesic forest). Results show that the wild dog has a relatively reduced turbinal surface area and a derived configuration of the turbinals that favors increased air flow to the lungs, and thus perhaps more rapid cooling of brain and body. This is consistent with its ability to run long distances at high speed and suggests that maxilloturbinal structure might be an osteological indicator of stamina in mammals.

A number of severe flooding events have occurred both in South Africa and internationally in recent years. Furthermore, changes in both the intensity and frequency of extreme rainfall events have been documented, both locally and internationally, associated with climate change. The recent loss of life, destruction of infrastructure, and associated economic losses caused by flooding, compounded by the probability of increased rainfall variability in the future, highlight that design flood estimation (DFE) techniques within South Africa are outdated and in need of revision. A National Flood Studies Programme (NFSP) has recently been initiated to overhaul DFE procedures in South Africa. One of the recommendations in the NFSP is the further development of a continuous simulation modelling (CSM) system for DFE in South Africa. The focus of this paper is a review of CSM techniques for DFE, to guide further development for application in South Africa. An introduction to DFE, and particularly the CSM approach, is presented, followed by a brief overview of DFE techniques used in South Africa, leading into a more detailed summary of CSM for DFE within South Africa to date. This is followed by a review of the development and application of CSM methods for DFE internationally, with a focus on the United Kingdom and Australia, where methods have been developed with the intention of national scale implementation. It is important to highlight that there is a plethora of CSM methods available internationally and this review is not exhaustive; it focuses on and identifies some of the strengths and weaknesses of several popular methods, particularly those intended for national scale application, as the intended outcome from this review is to identify a path towards the development of a usable national scale CSM system for DFE in South Africa. Emphasis on a usable method is important, considering the reality that, despite promising results, numerous benefits, and national scale methods being developed, it appears that the CSM method for DFE is rarely used in practice. [ABSTRACT FROM AUTHOR]

Design flood estimation (DFE) is essential in the planning and design of hydraulic structures. In South Africa, outdated methods are widely applied for DFE. In this paper the potential of a continuous simulation modelling (CSM) approach to DFE in South Africa, using the daily time-step ACRU agrohydrological model, is investigated. The paper focuses on the links and similarities between the SCS-SA and ACRU models and the subsequent preliminary investigations that were undertaken to account for and incorporate the land cover classes, including land management practices and hydrological condition, of the SCS-SA model into the ACRU CSM approach. The approach to this study was to investigate how design volumes simulated by the SCS-SA model for various land management practices or conditions could be simulated by the ACRU model. Since peak discharge estimation in both models is directly dependent on simulated volumes, this preliminary study focused only on design runoff volumes, with subsequent investigations on peak discharge required in future research. In the absence of observed data, design runoff volumes and changes in design runoff volumes, as simulated by the SCS-SA model, were used as a substitute for observed data, i.e., as a reference, to achieve similar design runoff volumes and changes in design volumes in the ACRU model. This was achieved by adjusting relevant input parameters in the ACRU model to represent the change in management practice or hydrological condition, as represented in the SCS-SA model. Following a sensitivity analysis of relevant ACRU parameters, calibration of 2 selected parameters against SCS-SA CN values for selected land cover classes was performed. A strong linear relationship (R2 = 0.94) between these ACRU parameters and SCS-SA CNs for selected land cover classes was found and consequently specific rules and equations were developed to represent SCS-SA land cover classes in ACRU. Recommendations are made to further validate and verify the approach and to further the development of a CSM system for DFE in South Africa. [ABSTRACT FROM AUTHOR]

Petitioner submitted Decedent's handwritten Will, dated March 15, 1999, which the Court found to be lawfully executed. The Will gave a specific devise and a specific bequest to Petitioner as Guardian of Decedent's dog and cat, and the Will contained no residuary clause. The heirs at law asked the Court to interpret the specific devise and specific bequest as an attempt by Decedent to create a pet trust, which the heirs at law argued would fail because pet trusts were not enforceable at the time the Will was executed. While the Court found a clear intent for Decedent's assets to be used for the pets' benefit, there was no clear indication of Decedent's intent to create a trust. The Court found that the Will lacked unambiguous trust language, contextual clues indicating an intention to create a trust, and the manifestation of a clear intention to create a trust. The Court held that the bequests transmit absolute gifts, free from definitive conditional or trust language. [ABSTRACT FROM AUTHOR]