Design and demonstration of a vari-focal optical see-through head-mounted display using freeform Alvarez lenses

Alvarez lenses offer accurate and high-speed, dynamic tuning of optical power through a lateral shifting of two lens elements, making them an appealing solution to eliminate the inherent decoupling of accommodation and convergence seen in conventional stereoscopic displays. In this paper, we present a design of a compact eyepiece coupled with two lateral-shifting freeform Alvarez lenses to enable a compact. high-resolution, optical see-through head-mounted display (HMD). The proposed design is able to tune its focal depth from 0 to 3 diopters, rendering near-accurate focus cues with high image quality and a large undistorted see-through field of view (FOV). Our design utilizes an 1920x1080 color resolution organic light-emitting diode (OLED) microdisplay to achieve a >30 degree virtual diagonal FOV, with an angular resolution of 0.4 contrast over the full field. We also experimentally demonstrate a fully functional benchtop prototype using mostly off-the-shelf optics. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing AgreementOpen access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Rapid Intrapreneurship with a Human Touch

The pace of change in digital organisations necessitates the adoption of rapid innovation practices. While rapid innovation is typically reactive to external uncertainties and shocks, firms that are capable of generating internal disruptions and innovating quickly can gain a competitive edge. This research investigates the role of intrapreneurship in promoting rapid innovation within an organisation's proprietary framework, employing an employee-led, human-centric approach. To explore this concept, the qualitative case study approach will be utilised, with MoMo, Vietnam's leading E-Wallet, serving as a prime example of an organisation that has successfully implemented such practices. Through an analysis of MoMo's internal processes and culture, this research aims to uncover the factors that contribute to the success of intrapreneurial endeavours and rapid innovation within digital organisations

Land-use affects the radiocarbon age, storage and depth distribution of soil organic carbon in Eastern Australia

Land-use has been shown to affect soil organic carbon (SOC) storage, with natural systems generally storing larger quantities of SOC than anthropogenically managed systems in surface soils. However, these effects are often difficult to detect deeper in the soil profile. Little is known regarding the effects of land-use on the radiocarbon age of SOC, both at the surface and deeper in the soil profile. We investigated the storage, radiocarbon content and depth distribution of soil organic carbon from across the state of NSW, Australia. A total of 100 profiles were analysed for total SOC concentration at numerous depths (up to 1 m) and a machine learning approach implementing tree ensemble methods was used to identify the key drivers of SOC depth distribution. Surface SOC storage was strongly associated with climate (predominately precipitation, to a lesser degree relative humidity and temperature), whereas SOC depth distribution was predominately influenced by land-use, soil type and to a lesser extent temperature. A subset of 12 soil profiles from a range of climate zones were analysed for radiocarbon content with a view to contrasting three land-use systems: natural, cleared/grazed and cropped. Radiocarbon content was affected strongly by land-use, with effects most pronounced at depth. Native systems appeared to have the youngest carbon throughout the profile, with cropped and grazed systems having older SOC. Radiocarbon content was also strongly associated with SOC content. Our results indicate that natural systems act as a carbon pump into the soil, injecting young, fresh organic carbon which is vertically distributed throughout the profile. In contrast, managed systems are deprived of this input and are depleted in SOC at all depths, leading to higher radiocarbon ages throughout the profile

Rapid Intrapreneurship with a Human Touch

The pace of change in digital organisations necessitates the adoption of rapid innovation practices. While rapid innovation is typically reactive to external uncertainties and shocks, firms that are capable of generating internal disruptions and innovating quickly can gain a competitive edge. This research investigates the role of intrapreneurship in promoting rapid innovation within an organisation\u27s proprietary framework, employing an employee-led, human-centric approach. To explore this concept, the qualitative case study approach will be utilised, with MoMo, Vietnam\u27s leading E-Wallet, serving as a prime example of an organisation that has successfully implemented such practices. Through an analysis of MoMo\u27s internal processes and culture, this research aims to uncover the factors that contribute to the success of intrapreneurial endeavours and rapid innovation within digital organisations

Application of sex-specific single-nucleotide polymorphism filters in genome-wide association data

We explored five sex-specific quality control filters in North American Rheumatoid Arthritis Consortium's Illumina 550 k datasets. Three X chromosome and three autosomal single-nucleotide polymorphisms flagged by sex quality control filters were missed by filters of call rate at 95% and Hardy-Weinberg equilibrium at 10-6. We applied a subset of these sex-specific quality control filters to eight chromosomes in the Framingham Heart Study samples genotyped by Affymetrix 500 k SNP arrays, and identified another two single-nucleotide polymorphisms that failed to be picked up by the above global filters

(1+1)-dimensional Baryons from the SU(N) Color-Flavor Transformation

The color-flavor transformation, an identity that connects two integrals, each of which is over one of a dual pair of Lie groups acting in the fermionic Fock space, is extended to the case of the special unitary group. Using this extension, a toy model of lattice QCD is studied: N_f species of spinless fermions interacting with strongly coupled SU(N_c) lattice gauge fields in 1+1 dimensions. The color-flavor transformed theory is expressed in terms of gauge singlets, the meson fields, organized into sectors distinguished by the distribution of baryonic flux. A comprehensive analytical and numerical search is made for saddle-point configurations of the meson fields, with various topological charges, in the vacuum and single-baryon sectors. Two definitions of the static baryon on the square lattice, straight and zigzag, are investigated. The masses of the baryonic states are estimated using the saddle-point approximation for large N_c.Comment: LateX, 53 pages, 13 figure

Trends in Roll-Your-Own Smoking: Findings from the ITC Four-Country Survey (2002–2008)

Objective. To establish the trends in prevalence, and correlates, of roll-your-own (RYO) use in Canada, USA, UK and Australia, 2002–2008. Methods. Participants were 19,456 cigarette smokers interviewed during the longitudinal International Tobacco Control (ITC) Four-Country Survey in Canada, USA, UK, and Australia. Results. “Predominant” RYO use (i.e., >50% of cigarettes smoked) increased significantly in the UK and USA as a proportion of all cigarette use (both P < .001) and in all countries as a proportion of any RYO use (all P < .010). Younger, financially stressed smokers are disproportionately contributing to “some” use (i.e., ≤50% of cigarettes smoked). Relative cost was the major reason given for using RYO, and predominant RYO use is consistently and significantly associated with low income. Conclusions. RYO market trends reflect the price advantages accruing to RYO (a product of favourable taxation regimes in some jurisdictions reinforced by the enhanced control over the amount of tobacco used), especially following the impact of the Global Financial Crisis; the availability of competing low-cost alternatives to RYO; accessibility of duty-free RYO tobacco; and tobacco industry niche marketing strategies. If policy makers want to ensure that the RYO option does not inhibit the fight to end the tobacco epidemic, especially amongst the disadvantaged, they need to reduce the price advantage, target additional health messages at (young) RYO users, and challenge niche marketing of RYO by the industry

12CO, 13CO and C18O observations along the major axes of nearby bright infrared galaxies

We present simultaneous observations of CO,13CO and C18O J=1-0 emission in 11 nearby (cz<1000 km/s) bright infrared galaxies. Both 12CO and 13CO are detected in the centers of all galaxies, except for 13CO in NGC 3031. We have also detected C18O, CS J=2-1, and HCO+ J=1-0 emission in the nuclear regions of M82 and M51. These are the first systematical extragalactic detections of 12CO and its isotopes from the PMO 14m telescope. We have conducted half-beam spacing mapping of M82 over an area of 4'*2.5' and major axis mapping of NGC 3627, NGC 3628, NGC 4631, and M51. The radial distributions of 12CO and 13CO in NGC 3627, NGC 3628, and M51 can be well fitted by an exponential profile. The 12CO/13CO intensity ratio,R,decreases monotonically with galactocentric radius in all mapped sources. The average R in the center and disk of the galaxies are 9.9+/-3.0 and 5.6+/-1.9 respectively, much lower than the peculiar R(~24) found in the center of M82. The intensity ratios of 13CO/C18O, 13CO/HCO+ and 13CO/CS (either ours or literature data) show little variations with galactocentric radius, in sharp contrast with the greatly varied R. This supports the notion that the observed gradient in R could be the results of the variations of the physical conditions across the disks. The H_2 column density derived from C18O shows that the Galactic standard conversion factor (X-factor) overestimates the amount of the molecular gas in M82 by a factor of ~2.5. These observations suggest that the X-factor in active star-forming regions (i.e., nuclear regions) should be lower than that in normal star-forming disks, and the gradient in R can be used to trace the variations of the X-factor.Comment: 27 pages, 7 figures, accepted by RA

Comparative characterization of the PvuRts1I family of restriction enzymes and their application in mapping genomic 5-hydroxymethylcytosine

PvuRts1I is a modification-dependent restriction endonuclease that recognizes 5-hydroxymethylcytosine (5hmC) as well as 5-glucosylhydroxymethylcytosine (5ghmC) in double-stranded DNA. Using PvuRts1I as the founding member, we define a family of homologous proteins with similar DNA modification-dependent recognition properties. At the sequence level, these proteins share a few uniquely conserved features. We show that these enzymes introduce a double-stranded cleavage at the 3′-side away from the recognized modified cytosine. The distances between the cleavage sites and the modified cytosine are fixed within a narrow range, with the majority being 11–13 nt away in the top strand and 9–10 nt away in the bottom strand. The recognition sites of these enzymes generally require two cytosines on opposite strand around the cleavage sites, i.e. 5′-CN11–13↓N9–10G-3′/3′-GN9–10↓N11–13C-5′, with at least one cytosine being modified for efficient cleavage. As one potential application for these enzymes is to provide useful tools for selectively mapping 5hmC sites, we have compared the relative selectivity of a few PvuRts1I family members towards different forms of modified cytosines. Our results show that the inherently different relative selectivity towards modified cytosines can have practical implications for their application. By using AbaSDFI, a PvuRts1I homolog with the highest relative selectivity towards 5ghmC, to analyze rat brain DNA, we show it is feasible to map genomic 5hmC sites close to base resolution. Our study offers unique tools for determining more accurate hydroxymethylomes in mammalian cells