Initial experience in self-monitoring of intraocular pressure.

Background/aims: Diurnal variation in intraocular pressure (IOP) is a routine assessment in glaucoma management. Providing patients the opportunity to perform self-tonometry might empower them and free hospital resource. We previously demonstrated that 74% of patients can use the Icare® HOME tonometer. This study further explores Icare® HOME patient self-monitoring. Methods: Patients were trained by standard protocol to use the Icare® HOME rebound tonometer. Patient self-tonometry was compared to Goldmann applanation tonometry (GAT) over one clinical day. Following this, each patient was instructed to undertake further data collection that evening and over the subsequent two days. Results: Eighteen patients (35 eyes) participated. Good agreement was demonstrated between GAT and Icare® HOME for IOPs up to 15 mm Hg. Above this IOP the Icare® tended to over-read, largely explained by 2 patients with corneal thickness >600 um. The mean peak IOP during ‘clinic hours’ phasing was 16.7 mm Hg and 18.5 mm Hg (p = 0.24) over three days. An average range of 5.0, 7.0 and 9.8 mm Hg was shown during single day clinic, single day home and three day home phasing respectively (p =<0.001). The range of IOP was lower in eyes with prior trabeculectomy (6.1 mm Hg vs 12.2 mm Hg). All patients undertook one reading in the early morning at home with an average of 4.8 readings during, and 3.1 readings after office hours. Conclusions: This small study shows that self-tonometry is feasible. The findings from home phasing demonstrated higher peak and trough IOPs, providing additional clinical information. Home phasing is a viable alternative. The cost-effectiveness of this approach has yet to be addressed

Early Advanced LIGO binary neutron-star sky localization and parameter estimation

2015 will see the first observations of Advanced LIGO and the start of the gravitational-wave (GW) advanced-detector era. One of the most promising sources for ground-based GW detectors are binary neutron-star (BNS) coalescences. In order to use any detections for astrophysics, we must understand the capabilities of our parameter-estimation analysis. By simulating the GWs from an astrophysically motivated population of BNSs, we examine the accuracy of parameter inferences in the early advanced-detector era. We find that sky location, which is important for electromagnetic follow-up, can be determined rapidly (~5 s), but that sky areas may be hundreds of square degrees. The degeneracy between component mass and spin means there is significant uncertainty for measurements of the individual masses and spins; however, the chirp mass is well measured (typically better than 0.1%).Comment: 4 pages, 2 figures. Published in the proceedings of Amaldi 1

Supplement: Going the Distance: Mapping Host Galaxies of LIGO and Virgo Sources in Three Dimensions Using Local Cosmography and Targeted Follow-up

This is a supplement to the Letter of Singer et al. (https://arxiv.org/abs/1603.07333), in which we demonstrated a rapid algorithm for obtaining joint 3D estimates of sky location and luminosity distance from observations of binary neutron star mergers with Advanced LIGO and Virgo. We argued that combining the reconstructed volumes with positions and redshifts of possible host galaxies can provide large-aperture but small field of view instruments with a manageable list of targets to search for optical or infrared emission. In this Supplement, we document the new HEALPix-based file format for 3D localizations of gravitational-wave transients. We include Python sample code to show the reader how to perform simple manipulations of the 3D sky maps and extract ranked lists of likely host galaxies. Finally, we include mathematical details of the rapid volume reconstruction algorithm.Comment: For associated data release, see http://asd.gsfc.nasa.gov/Leo.Singer/going-the-distanc

Accuracy of inference on the physics of binary evolution from gravitational-wave observations

The properties of the population of merging binary black holes encode some of the uncertain physics of the evolution of massive stars in binaries. The binary black hole merger rate and chirp mass distribution are being measured by ground-based gravitational-wave detectors. We consider isolated binary evolution and explore how accurately the physical model can be constrained with such observations by applying the Fisher information matrix to the merging black hole population simulated with the rapid binary population synthesis code COMPAS. We investigate variations in four COMPAS parameters: common envelope efficiency, kick velocity dispersion, and mass loss rates during the luminous blue variable and Wolf--Rayet stellar evolutionary phases. We find that 1000 observations would constrain these model parameters to a fractional accuracy of a few percent. Given the empirically determined binary black hole merger rate, we can expect gravitational-wave observations alone to place strong constraints on the physics of stellar and binary evolution within a few years.Comment: 12 pages, 9 figures; version accepted by Monthly Notices of the Royal Astronomical Societ

Experimental study of idler roll slippage

Idler roll slippage occurs when the roll surface velocity no longer equals the velocity of the web that transports the roll. In a web transport system, slippage will produce scratches in sensitive, coated web or cause process problems such as loss of lateral tracking. This paper presents the results of an experimental study on roll slippage with polyester film and several different roll surfaces at web speeds to 1000 fpm.A test stand was installed in a laboratory based web transport line. This allowed for the control of tension and the continuous measurement of torque, tensions and speeds. Tests were conducted using four different polyester films. Roll surfaces that were tested consisted of ground metal, rubber covered, grooved and knurled. The effects of wrap angle and outgoing tension were also studied.Slippage was found to vary continuously from 0.05 to 100% depending on the amount of applied braking torque. The parameter used to quantify the onset of slippage was "effective coefficient of friction". It was determined experimentally when the difference between web velocity and roll velocity was 0.25% of the web velocity. Reasons for this definition are discussed in the paper. The standard belt equation was used to calculate the coefficient from the test results. The change in the coefficient with web velocity, roll surface, wrap angle and film surface are presented. A roughened knurled roll provided the most traction and had fewer tendencies to slip at higher speeds

Spaceborne radar observations: A guide for Magellan radar-image analysis

Geologic analyses of spaceborne radar images of Earth are reviewed and summarized with respect to detecting, mapping, and interpreting impact craters, volcanic landforms, eolian and subsurface features, and tectonic landforms. Interpretations are illustrated mostly with Seasat synthetic aperture radar and shuttle-imaging-radar images. Analogies are drawn for the potential interpretation of radar images of Venus, with emphasis on the effects of variation in Magellan look angle with Venusian latitude. In each landform category, differences in feature perception and interpretive capability are related to variations in imaging geometry, spatial resolution, and wavelength of the imaging radar systems. Impact craters and other radially symmetrical features may show apparent bilateral symmetry parallel to the illumination vector at low look angles. The styles of eruption and the emplacement of major and minor volcanic constructs can be interpreted from morphological features observed in images. Radar responses that are governed by small-scale surface roughness may serve to distinguish flow types, but do not provide unambiguous information. Imaging of sand dunes is rigorously constrained by specific angular relations between the illumination vector and the orientation and angle of repose of the dune faces, but is independent of radar wavelength. With a single look angle, conditions that enable shallow subsurface imaging to occur do not provide the information necessary to determine whether the radar has recorded surface or subsurface features. The topographic linearity of many tectonic landforms is enhanced on images at regional and local scales, but the detection of structural detail is a strong function of illumination direction. Nontopographic tectonic lineaments may appear in response to contrasts in small-surface roughness or dielectric constant. The breakpoint for rough surfaces will vary by about 25 percent through the Magellan viewing geometries from low to high Venusian latitudes. Examples of anomalies and system artifacts that can affect image interpretation are described

Conceptualizing Cybercrime: Definitions, Typologies and Taxonomies

Cybercrime is becoming ever more pervasive and yet the lack of consensus surrounding what constitutes a cybercrime has a significant impact on society, legal and policy response, and academic research. Difficulties in understanding cybercrime begin with the variability in terminology and lack of consistency in cybercrime legislation across jurisdictions. In this review, using a structured literature review methodology, key cybercrime definitions, typologies and taxonomies were identified across a range of academic and non-academic (grey literature) sources. The findings of this review were consolidated and presented in the form of a new classification framework to understand cybercrime and cyberdeviance. Existing definitions, typologies and taxonomies were evaluated, and key challenges were identified. Whilst conceptualizing cybercrime will likely remain a challenge, this review provides recommendations for future work to advance towards a universal understanding of cybercrime phenomena as well as a robust and comprehensive classification system

Intention to Hack? Applying the Theory of Planned Behaviour to Youth Criminal Hacking

Adolescents are currently the most digitally connected generation in history. There is an ever-growing need to understand how typical adolescent risk-taking intersects with the vastly criminogenic potential of digital technology. Criminal hacking in older adolescents (16–19-year-olds) was assessed using an adapted Theory of Planned Behaviour (TPB) model, a cohesive theoretical framework that incorporates cognitive processes and human drivers (informed by psychology, cyberpsychology, and criminology theory). In 2021, a large-scale anonymous online survey was conducted across nine European countries. Criminal hacking was assessed using data from 3985 participants (M = 1895, 47.55%; F = 1968, 49.39%). This study formulated a powerful predictive model of youth hacking intention (accounting for 38.8% of the variance) and behaviour (accounting for 33.6% of the variance). A significant minority, approximately one in six (16.34%), were found to have engaged in hacking, and approximately 2% reported engaging in hacking often or very often. Increased age, being male, and offline deviant behaviour were significant predictors of hacking behaviour. In line with the TPB, intention was the strongest individual predictor of hacking behaviour, which in turn was significantly predicted by cognitive processes accounted for by TPB constructs: subjective norms of family and peers, attitudes towards hacking, and perceived behavioural control. These TPB constructs were found to be significantly associated with human factors of risk-taking, toxic online disinhibition, offline deviant behaviour, and demographic variables of age and gender. Implications for future research, interventions, policy, and practice are discussed