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Purpose To assess accuracy and adherence of visual field (VF) home monitoring in a pilot sample of patients with glaucoma. Design Prospective longitudinal feasibility and reliability study. Methods Twenty adults (median 71 years) with an established diagnosis of glaucoma were issued a tablet perimeter (Eyecatcher) and were asked to perform 1 VF home assessment per eye, per month, for 6 months (12 tests total). Before and after home monitoring, 2 VF assessments were performed in clinic using standard automated perimetry (4 tests total, per eye). Results All 20 participants could perform monthly home monitoring, though 1 participant stopped after 4 months (adherence: 98% of tests). There was good concordance between VFs measured at home and in the clinic (r = 0.94, P Conclusions Home monitoring of VFs is viable for some patients and may provide clinically useful data.

In instances of asymmetric peripheral vision loss (e.g., glaucoma), binocular performance on simple psychophysical tasks (e.g., static threshold perimetry) is well-predicted by the better seeing eye alone. This suggests that peripheral vision is largely ‘better-eye limited’. In the present study, we examine whether this also holds true for real-world tasks, or whether even a degraded fellow eye contributes important information for tasks of daily living. Twelve normally-sighted adults performed an everyday visually-guided action (finding a mobile phone) in a virtual-reality domestic environment, while levels of peripheral vision loss were independently manipulated in each eye (gaze-contingent blur). The results showed that even when vision in the better eye was held constant, participants were significantly slower to locate the target, and made significantly more head- and eye-movements, as peripheral vision loss in the worse eye increased. A purely unilateral peripheral impairment increased response times by up to 25%, although the effect of bilateral vision loss was much greater (>200%). These findings indicate that even a degraded visual field still contributes important information for performing everyday visually-guided actions. This may have clinical implications for how patients with visual field loss are managed or prioritized, and for our understanding of how binocular information in the periphery is integrated.

Summary: Background: We undertook a Grand Challenges in Global Eye Health prioritisation exercise to identify the key issues that must be addressed to improve eye health in the context of an ageing population, to eliminate persistent inequities in health-care access, and to mitigate widespread resource limitations. Methods: Drawing on methods used in previous Grand Challenges studies, we used a multi-step recruitment strategy to assemble a diverse panel of individuals from a range of disciplines relevant to global eye health from all regions globally to participate in a three-round, online, Delphi-like, prioritisation process to nominate and rank challenges in global eye health. Through this process, we developed both global and regional priority lists. Findings: Between Sept 1 and Dec 12, 2019, 470 individuals complete round 1 of the process, of whom 336 completed all three rounds (round 2 between Feb 26 and March 18, 2020, and round 3 between April 2 and April 25, 2020) 156 (46%) of 336 were women, 180 (54%) were men. The proportion of participants who worked in each region ranged from 104 (31%) in sub-Saharan Africa to 21 (6%) in central Europe, eastern Europe, and in central Asia. Of 85 unique challenges identified after round 1, 16 challenges were prioritised at the global level; six focused on detection and treatment of conditions (cataract, refractive error, glaucoma, diabetic retinopathy, services for children and screening for early detection), two focused on addressing shortages in human resource capacity, five on other health service and policy factors (including strengthening policies, integration, health information systems, and budget allocation), and three on improving access to care and promoting equity. Interpretation: This list of Grand Challenges serves as a starting point for immediate action by funders to guide investment in research and innovation in eye health. It challenges researchers, clinicians, and policy makers to build collaborations to address specific challenges. Funding: The Queen Elizabeth Diamond Jubilee Trust, Moorfields Eye Charity, National Institute for Health Research Moorfields Biomedical Research Centre, Wellcome Trust, Sightsavers, The Fred Hollows Foundation, The Seva Foundation, British Council for the Prevention of Blindness, and Christian Blind Mission. Translations: For the French, Spanish, Chinese, Portuguese, Arabic and Persian translations of the abstract see Supplementary Materials section.

This study evaluated the feasibility of using a ‘self-calibrating’ display (EIZO CG277) to perform screen-based threshold perimetry. Such displays incorporate their own integrated photometer, so could potentially be used ‘straight out of the box’, without the need for time-consuming and costly luminance calibration by skilled experts. Concerns remain, however, due to the fact that the internal calibration of such devices is imperfect, and lingering doubts regarding the accuracy of screen-based perimetry in general. To evaluate such a system, automated static threshold perimetry was performed in thirty-two normal-sighted adults. In one condition, participants performed a novel screen-based perimetry test, for which the screen was calibrated extensively using traditional photometric techniques/equipment. In a second condition, the same test was performed, but the display was calibrated using only the screen’s integrated photometer (and assuming uniformity across the display). For reference, participants also completed a traditional visual-field assessment using a Humphrey Field Analyzer (HFA). All three tests were performed twice to assess test-retest repeatability (six tests total). The results showed no differences when comparing screen-based perimetric measurements made with internal self-calibration vs full manual calibration (either in terms of mean sensitivity, pointwise sensitivity, test-retest repeatability, or test duration). Furthermore, the accuracy and precision of both were indistinguishable from the current gold standard (HFA), although the HFA was approximately two minutes (~30%) faster. These results indicate that self-calibrating commercial monitors can be used to perform screen-based perimetry almost as well as current clinical devices, and without the need for any specialized knowledge or equipment to setup or maintain. This could facilitate perimetric testing in currently hard-to-reach settings, such as community centers, stroke wards, homes, rural locations, or developing countries.

The Southern Irumide Belt (SIB) of Zambia consists of predominantly Mesoproterozoic terranes that record a pervasive tectono-metamorphic overprint from collision between the Congo and Kalahari cratons in the final stages of Gondwana amalgamation. This study applies multi-method thermochronology to samples throughout southern Zambia to constrain the post-collisional, Phanerozoic thermo-tectonic evolution of the region. U-Pb apatite and 40Ar/39Ar muscovite data are used to constrain the cooling history of the region following Congo–Kalahari collision, and reveal ages of c. 550–450 Ma. Variations in the recorded cooling ages are interpreted to relate to localised post-tectonic magmatism and the proximity of analysed samples to the Congo–Kalahari suture. Apatite fission track data are used to constrain the low-temperature thermo-tectonic evolution of the region and identify mean central ages of c. 320–300, 210–200 and 120–110 Ma. Thermal modelling of these samples identifies a number of thermal events occurring in the region throughout the Phanerozoic. Carboniferous to Permian–Triassic heating is suggested to relate to the development of Karoo rift basins found throughout central Africa and constrain the timing of sedimentation in the basin. Permian to Jurassic cooling is identified in a number of samples, reflecting exhumation as a result of the Mauritanian–Variscan and Gondwanide orogenies. Subsequent cooling of the majority of samples occurs from the Cretaceous and persists until present, reflecting exhumation in response to larger scale rifting associated with the break-up of Gondwana. Each model reveals a later phase of enhanced cooling beginning at c. 30 Ma that, if not an artefact of modelling, corresponds to the development of the East African Rift System. The obtained thermochronological data elucidate the previously unconstrained thermal evolution of the SIB, and provides a refined regional framework for constraining the tectonic history of central Africa throughout the Phanerozoic.

Objective To review the literature systematically and perform meta-analyses to address these questions: 1) Is there evidence that self-measured blood pressure (BP) without other augmentation is superior to office-based measurement of BP for achieving better BP control or for preventing adverse clinical outcomes that are related to elevated BP? 2) What is the optimal target for BP lowering during antihypertensive therapy in adults? 3) In adults with hypertension, how do various antihypertensive drug classes differ in their benefits and harms compared with each other as first-line therapy? Methods Electronic literature searches were performed by Doctor Evidence, a global medical evidence software and services company, across PubMed and EMBASE from 1966 to 2015 using key words and relevant subject headings for randomized controlled trials that met eligibility criteria defined for each question. We performed analyses using traditional frequentist statistical and Bayesian approaches, including random-effects Bayesian network meta-analyses. Results Our results suggest that: 1) There is a modest but significant improvement in systolic BP in randomized controlled trials of self-measured BP versus usual care at 6 but not 12 months, and for selected patients and their providers self-measured BP may be a helpful adjunct to routine office care. 2) systolic BP lowering to a target of

Fluid inclusion and mineral thermobarometric study supplemented by U-Th-total Pb monazite dating has been carried out in country rocks of the Evate carbonatite, which is an example of a Neoproterozoic (~590 Ma) orogenic carbonatite formed within a post-collisional tectonic setting in the Monapo granulite complex of NE Mozambique. The fluid inclusion analysis of a 573 ± 13 Ma old fenite subjacent to the Evate carbonatite revealed primary, high-density to superdense CO2-rich fluids (>1 g.cm−3) with minor admixtures of N2 (0–17.5 mol%) and CH4 (0–1.1 mol%) accompanied by alkalic hydrocarbonate melts and aqueous fluids with minor sulphates. Isochores of CO2 inclusions intersected by isopleths calculated from Ti-in-quartz and Zr-in-rutile thermometers indicate fenite formation at 480–530 °C and 2.1–5.4 kbar. The CO2-rich gas of the fenite-forming fluids/melts is similar to the anhydrous CO2 gas with traces of N2 (

Perceptual learning has traditionally been portrayed as a bottom-up phenomenon that improves encoding or decoding of the trained stimulus. Cognitive skills such as attention and memory are thought to drive, guide and modulate learning but are, with notable exceptions, not generally considered to undergo changes themselves as a result of training with simple perceptual tasks. Moreover, shifts in threshold are interpreted as shifts in perceptual sensitivity, with no consideration for non-sensory factors (such as response bias) that may contribute to these changes. Accumulating evidence from our own research and others shows that perceptual learning is a conglomeration of effects, with training-induced changes ranging from the lowest (noise reduction in the phase locking of auditory signals) to the highest (working memory capacity) level of processing, and includes contributions from non-sensory factors that affect decision making even on a “simple” auditory task such as frequency discrimination. We discuss our emerging view of learning as a process that increases the signal-to-noise ratio associated with perceptual tasks by tackling noise sources and inefficiencies that cause performance bottlenecks, and present some implications for training populations other than young, smart, attentive and highly-motivated college students.

A new high-performance metrology gantry system has been developed within the scope of collaborative efforts of optics groups at the US Department of Energy synchrotron radiation facilities as well as the BESSY-II synchrotron at the Helmholtz Zentrum Berlin (Germany) and the participation of industrial vendors of x-ray optics and metrology instrumentation directed to create a new generation of optical slope measuring systems (OSMS) [1]. The slope measurement accuracy of the OSMS is expected to be The fabricated system was installed and commissioned (December 2012) at the Advanced Photon Source (APS) at Argonne National Laboratory to replace the aging APS Long Trace Profiler (APS LTP-II). Preliminary tests were conducted (in January and May 2012) using the optical system configuration of the Nanometer Optical Component Measuring Machine (NOM) developed at Helmholtz Zentrum Berlin (HZB)/BESSY-II. With a flat Si mirror that is 350 mm long and has 200 nrad rms nominal slope error over a useful length of 300 mm, the system provides a repeatability of about 53 nrad. This value corresponds to the design performance of 50 nrad rms accuracy for inspection of ultra-precise flat optics.

SummaryMammalian navigation depends both on visual landmarks and on self-generated (e.g., vestibular and proprioceptive) cues that signal the organism's own movement [1–5]. When these conflict, landmarks can either reset estimates of self-motion or be integrated with them [6–9]. We asked how humans combine these information sources and whether children, who use both from a young age [10–12], combine them as adults do. Participants attempted to return an object to its original place in an arena when given either visual landmarks only, nonvisual self-motion information only, or both. Adults, but not 4- to 5-year-olds or 7- to 8-year-olds, reduced their response variance when both information sources were available. In an additional “conflict” condition that measured relative reliance on landmarks and self-motion, we predicted behavior under two models: integration (weighted averaging) of the cues and alternation between them. Adults' behavior was predicted by integration, in which the cues were weighted nearly optimally to reduce variance, whereas children's behavior was predicted by alternation. These results suggest that development of individual spatial-representational systems precedes development of the capacity to combine these within a common reference frame. Humans can integrate spatial cues nearly optimally to navigate, but this ability depends on an extended developmental process.

Hard X-ray imaging with synchrotron radiation is a powerful tool to study opaque materials on the micro- and nano-lengthscales. Different imaging methods are available with an instrument recently built at Sector 34 of the Advanced Photon Source. In-line phase contrast imaging is performed with micrometer resolution. Increased spatial resolution is achieved using cone-beam geometry. The almost parallel beam is focused with a Kirkpatrick–Baez mirror system. The focal spot serves as a diverging secondary source. An X-ray magnified image of the sample is projected on the detector. For imaging and tomography with sub-100 nm resolution, an X-ray full-field microscope has been built. It uses a Kirkpatrick–Baez mirror (KB) as a condenser optic, followed by a micro-Fresnel zone plate (FZP) as an objective lens. The zone plates presently provide 50–85 nm spatial resolution when operating the microscope with photon energy between 6 and 12 keV. Tomography experiments have been performed with this new device. � 2007 Published by Elsevier B.V.

Small-angle light and X-ray scattering are used to study the morphology of reinforcing fillers in organic rubbers. The data, which extend over six orders of magnitude in length scale, reveal a complex morphology of the powders consisting of primary particles, aggregates and agglomerates. The fragility of the agglomerates is assessed by observation of partial agglomerate disruption after exposure to intense ultrasound. Upon incorporation into rubber by mechanical mixing, the agglomerates break down all the way to the aggregates. The results are used to outline opportunities to exploit the growth processes underlying the complex structure to optimize the morphology for composite applications. Soft agglomerates that easily break down to aggregates, for example, aid in dispersion of reinforcing fillers in rubbers. The high surface area of the primaries, on the other hand, can be used to adjust the interaction between the rubber and the filler in order to control dynamic mechanical response of the filled rubber.

The tensile creep behavior of a Lu-doped silicon nitride was studied in the temperature range 1400–1550 � C with test periods of up to 10 200 h. Strain rates were 3–4 orders of magnitude less than those for Yb-doped grades of silicon nitride under the same conditions, suggesting a potential for prolonged operation of this material at temperatures up to 1470 � C. The stress exponent, n, and the activation energy, Q, for creep are 5.3� 2.0 and (757� 117) kJ/mol, respectively. Precise density and ultra-small-angle X-ray scattering measurements revealed that, in contrast to other grades of silicon nitride, cavitation could not be detected in the material studied. Redistribution of the secondary phases via solution-precipitation combined with grain boundary sliding is discussed as a possible creep mechanism. A discussion of the effect of Lu on viscosity indicates that replacement of Y by Lu may explain the improvement of creep behavior. # 2002 Published by Elsevier Science Ltd.

We present a data acquisition system to perform on-the-fly background subtraction and lower-level discrimination compression of streaming X-ray photon correlation spectroscopy (XPCS) data from a fast charge-coupled device area detector. The system is built using a commercial frame grabber with an on-board field-programmable gate array (FPGA). The system is capable of continuously processing 60 CCD frames per second each consisting of 1024×1024 pixels with up to 64 512 photon hits per frame.

We report the basic beamline design and current status of a new full-field X-ray imaging facility at Sector 32 of the Advanced Photon Source. The beamline consists of an existing hutch at 40 m and a new experiment enclosure at 77 m from the source, with both monochromatic and white-beam undulator X-ray capabilities. Experimental programs being planned for the beamline include high-speed time-resolved imaging, phase-contrast and coherent imaging, diffraction-enhanced imaging, ultra-small-angle scattering imaging, and phase- and absorption-contrast transmission X-ray microscopy.

The size distribution and volume fraction of Cr23C6 precipitates in 9Cr-1MoVNb steel have been isolated from the distributions of all other precipitates by the technique of anomalous small-angle X-ray scattering. Three X-ray wavelengths near the Cr K absorption edge were used to vary the scattering contrast of Cr23C6 while that of the other precipitates was left unchanged. Size distributions calculated from each scattering curve using a maximum entropy method were combined by a scattering contrast gradient analysis to isolate the volume-fraction size distribution of the chromium carbides. Behavior of these carbides was studied as a function of isothermal aging temperature. Mean diameter is smallest and Cr23C6 number density is highest after aging at 811 K. Above 811 K, the mean diameter of the chromium carbides increases with increasing aging temperature.

Modern third generation synchrotron radiation facilities are designed to provide sources of extremely high brilliance. We describe the properties of such brilliant sources that enable optimised experiments to be carried out in the field of materials research. In particular, we describe the planned programme and experimental facilities of the materials research collaborative access team at the advanced photon source (APS) currently under construction at the Argonne National Laboratory, Chicago, USA.

Many migratory birds make large detours to avoid crossing so-called ‘ecological barriers’ (usually vast expanses of sea, sand or ice). They do this in spite of being capable of storing enough fat as fuel to cross such areas in a single nonstop flight. Previous explanations for the adoption of circuitous migration routes by so many species involved factors such as wind and weather conditions and the risks of starvation or predation. New, surprisingly simple models by Thomas Alerstam 1xDetours in Bird Migration. Alerstam, T. J. Theor. Biol. 2001; 209: 319–331Crossref | PubMed | Scopus (123)See all References, based on the mass-dependent costs of flight derived from flight mechanical theory, now provide a general explanation for such detours and make quantitative predictions about their possible benefits.The explanation is based on the fact that travelling light and stopping often to refuel uses less energy than does a single long-haul flight with a heavy fuel load. Large fuel loads increase the cost of flapping flight because a fat bird weighs more and has a larger frontal area, incurring greater induced and parasitic drag. Thus, the added benefit, in terms of the additional flight range, of a given amount of fuel decreases with the fuel load that is already stored. As a result, birds should avoid routes that require nonstop flight across barriers in favour of those that can be covered by a series of short flights with a negligible fuel load and frequent refuelling, even if these journeys are longer.How big a detour can a bird make and still save energy? This depends on the barrier width and the fuel load necessary to cross it nonstop versus the number of steps, and hence fuel load carried, along the alternative route. For example, a bird requiring an 80% increase in mass above lean weight to cross a barrier nonstop would save energy by migrating along a detour that is up to 22% longer if the journey comprises two equal stages, or up to 57% longer if completed by numerous short flights.For many species with very different migration routes, the observed detours do conform to the model predictions. Red-backed shrikes Lanius collurio migrating from southeastern France to Tanzania reduce their barrier crossing by half by detouring round the eastern Mediterranean – a reduction that more than compensates for the extra energy costs associated with the additional distance of the detour. The model predictions hold for wheatears Oenanthe oenanthe crossing the East Atlantic between Greenland and Senegal and brent geese Branta bernicla migrating from the Wadden Sea to northern Russia. It is, however, not a universal explanation: American warblers, which skirt the Gulf of Mexico rather than crossing it, are following a detour that is clearly unfavourable in terms of fuel economy and which might have evolved in response to risk factors.Alerstam's models suggest that, for many birds, the aerodynamic cost of heavy fat loads has been an important factor in the evolution of detours to avoid ecological barriers. His work now offers a plausible null model against which other explanations should be tested.

A bullous retinal detachment with breaks in all quadrants developed in the right eye of a 72-year-old man four weeks after he had undergone cataract extraction. The retina was reattached successfully with a 360-degree scleral buckle. Four weeks later, the retina had redetached and developed fixed folds and broad equatorial membranes. These features and the hazy vitreous suggested massive periretinal proliferation. Fourteen days later, the patient's visual acuity suddenly improved and an examination disclosed that the retina had spontaneously reattached. Visual acuity was 6/12 (20/40) and has remained stable for 14 months.