Machine division

Techniques are generally described that include methods, devices, systems and/or apparatus for dividing a numerator by a denominator. Some example methods may include selecting a first numerical factor stored in an electronic storage media. The first numerical factor may be multiplied by a numerator at least in part using a first logic circuit configured to perform multiplication. The first numerical factor may also be multiplied by a denominator. A second numerical factor may be calculated based, at least in part, on an approximation of a square of the difference between unity and the product of the first numerical factor and the denominator. The second numerical factor may be multiplied by the product of the numerator and the first numerical factor at least in part using the first logic circuit, to generate an approximation of a quotient of the numerator and the denominator.Board of Regents, University of Texas Syste

Correlation of materials properties with the atomic density concept

Based on the hypothesis that the number of atoms per unit volume, accurately calculable for any substance of known real density and chemical composition, various characterizing parameters (energy levels of electrons interacting among atoms of the same or different kinds, atomic mass, bond intensity) were chosen for study. A multiple exponential equation was derived to express the relationship. Various properties were examined, and correlated with the various parameters. Some of the properties considered were: (1) heat of atomization, (2) boiling point, (3) melting point, (4) shear elastic modulus of cubic crystals, (5) thermal conductivity, and (6) refractive index for transparent substances. The solid elements and alkali halides were the materials studied. It is concluded that the number of different properties can quantitively be described by a common group of parameters for the solid elements, and a wide variety of compounds

The first ICASE/LARC industry roundtable: Session proceedings

The first 'ICASE/LaRC Industry Roundtable' was held on October 3-4, 1994, in Williamsburg, Virginia. The main purpose of the roundtable was to draw attention of ICASE/LaRC scientists to industrial research agendas. The roundtable was attended by about 200 scientists, 30% from NASA Langley; 20% from universities; 17% NASA Langley contractors (including ICASE personnel); and the remainder from federal agencies other than NASA Langley. The technical areas covered reflected the major research programs in ICASE and closely associated NASA branches. About 80% of the speakers were from industry. This report is a compilation of the session summaries prepared by the session chairmen

Gene-environment and gene-gene interactions in myopia

Motivated by the release of the UK Biobank data and the lack of documented gene-environment (GxE) and gene-gene (GxG) interactions in myopia, I sought to apply various statistical tools to provide a quantitative assessment of the interplay between environmental and genetic risk factors shaping refractive error. The comparison between the two different risk measurement scales with which GxE interactions can be identified suggested that the additive risk scale can lead to a more informative perspective about refractive error aetiology. The evaluation of two indirect methods for detecting genetic variants affecting refractive error via interaction effects suggested the enrichment of GxG and GxE among the variants that display marginal SNP effects. For genetic variants already known from prior GWAS studies to influence refractive error, genetic effect sizes were highly non-uniform; individuals from the tails of the refractive error distribution (i.e. high myopes and hyperopes) displayed much larger effects compared to individuals in the middle of the distribution (i.e. emmetropes). Prediction of refractive error using GxE interactions indicated that although some of the variance of refractive error could be explained by a risk score constructed using interaction effects, the contribution of GxE was already accounted for by a risk score constructed using marginal SNP effects only. Although a handful of candidate genes were identified using multifactor dimensionality reduction technique, none displayed compelling evidence of involvement in a GxG interaction. There was, however, suggestive evidence that the candidate genes constitute a genetic interaction network which is regulated by hub gene ZMAT4. In summary, the analyses reported in this thesis provide further support for the challenging nature of definitively identifying loci involved in GxE and GxG interactions. The thesis provides several guidelines that future studies could take into account to obtain more insightful results regarding the extent of interactions in refractive error

Undergraduate Bulletin, 2023-2024

https://red.mnstate.edu/bulletins/1107/thumbnail.jp

Undergraduate Bulletin, 2022-2023

https://red.mnstate.edu/bulletins/1106/thumbnail.jp

Biomechanical aspects of the anterior segment in human myopia

The thesis investigates the relationship between the biomechanical properties of the anterior human sclera and cornea in vivo using Schiotz tonometry (ST), rebound tonometry (RBT, iCare) and the Ocular Response Analyser (ORA, Reichert). Significant differences in properties were found to occur between scleral quadrants. Structural correlates for the differences were examined using Partial Coherent Interferometry (IOLMaster, Zeiss), Optical Coherent tomography (Visante OCT), rotating Scheimpflug photography (Pentacam, Oculus) and 3-D Magnetic Resonance Imaging (MRI). Subject groups were employed that allowed investigation of variation pertaining to ethnicity and refractive error. One hundred thirty-five young adult subjects were drawn from three ethnic groups: British-White (BW), British-South-Asian (BSA) and Hong-Kong-Chinese (HKC) comprising non-myopes and myopes. Principal observations: ST demonstrated significant regional variation in scleral resistance a) with lowest levels at quadrant superior-temporal and highest at inferior-nasal; b) with distance from the limbus, anterior locations showing greater resistance. Variations in resistance using RBT were similar to those found with ST; however the predominantly myopic HKC group had a greater overall mean resistance when compared to the BW-BSA group. OCT-derived scleral thickness measurements indicated the sclera to be thinner superiorly than inferiorly. Thickness varied with distance from the corneolimbal junction, with a decline from 1 to 2 mm followed by a successive increase from 3 to 7 mm. ORA data varied with ethnicity and refractive status; whilst axial length (AL) was associated with corneal biometrics for BW-BSA individuals it was associated with IOP in the HKC individuals. Complex interrelationships were found between ORA Additional-Waveform-Parameters and biometric data provided by the Pentacam. OCT indicated ciliary muscle thickness to be greater in myopia and more directly linked to posterior ocular volume (from MRI) than AL. Temporal surface areas (SAs, from MRI) were significantly smaller than nasal SAs in myopic eyes; globe bulbosity (from MRI) was constant across quadrants

The genetic associations of rhegmatogenous retinal detachment and ectopia lentis

A genetic predisposition to Rhegmatogenous Retinal Detachment (RD) has been suggested for over 40 years. Ectopia Lentis (EL) is known to have a genetic aetiology as part of Marfan Syndrome, other ocular syndromes and when occurring in isolation. This work investigates the genetic aetiology to these conditions in Mendelian and non Mendelian inheritance. The work in this thesis establishes a clear genotype-phenotype correlation between isolated EL and its most important causative gene: ADAMTSL4. This suggests that mutations in this gene result in a more severe phenotype than other genes causing EL. In doing so, a novel clinical grading system for this condition has also been developed. The expression of ADAMTSL4 and distribution of its protein within ocular tissue has also been investigated and suggests further roles for this protein in ocular development. Modelling of the protein was undertaken and provides insights for future investigations. Traditional and novel next generation investigative tools have also been employed to examine families with Mendelian inherited phenotypes including RD and EL. The role of a deleted exon in ADAMTS17 has been identified as playing a role in Weill-Marchesani Like syndrome. A novel ocular phenotype has also been defined in three families demonstrated to be caused by mutations in ADAMTS1 8. This gene has previously been described in few probands with ophthalmic phenotypes, and this work has further delineated the role of this gene. It is becoming clear that members of the ADAMTS family of proteins play a significant role in ocular development. Finally, over 1300 probands with non-Mendelian RD were recruited and closely phenotyped as part of this work. It has demonstrated novel racial differences in the phenotypes of those affected. This cohort contributed significantly towards the first genome wide association study (GWAS) into RD; and established for the first time the genetic contribution to this condition. Further funding has now been acquired to investigate this cohort further using a novel exome array. Preliminary quality control analysis has been performed; allowing a platform for further detailed analysis to identify putative functional variants associated with RD