Magnitude Of Offset Research Articles

Distribution of angle alpha and angle kappa offsets among adult candidates for cataract surgery.

The current study aimed to describe the distribution of angle alpha and angle kappa offsets as well as their associated ocular biometric parameters in a large population of candidates for cataract surgery. This cross-sectional retrospective study included 8,119 eyes of 4,781 candidates for cataract surgery (mean age 70.7 ± 12.9 years). There were 49.9% right eyes, and 53.0% patients were females. The angles offset and ocular biometric parameters were measured by the IOLMaster 700 (Carl Zeiss Meditec, AG, Germany). Patient's age and gender, and most of their ocular biometric measurements were similar for the right and left eyes except for pupil diameter (4.01 ± 1.18 vs. 3.92 ± 1.14 mm, respectively, P< 0.001). The angle alpha offset magnitude was similar for the right and left eyes (0.50 ± 0.20 and 0.51 ± 0.21 mm, P= 0.08), whereas the angle kappa offset magnitude was greater in the right eyes (0.37 ± 0.21 vs. 0.33 ± 0.20 mm, P< 0.001). The angle kappa offset magnitudes were greater in the right eyes compared to the left eyes for both males (0.36 ± 0.21 vs. 0.33 ± 0.21 mm, respectively, P< 0.001) and females (0.37 ± 0.20 vs. 0.34 ± 0.20 mm, respectively, P< 0.001). The offset magnitudes of both angles varied significantly according to gender, eye laterality, angle location, and biometric parameters (e.g., axial length). The offset magnitudes of both angles were positively correlated in both right and left eyes. The offset magnitudes of both the angle alpha and angle kappa present significant variations according to gender, eye laterality, angle location, and biometric parameters, such as AL. These values are also population-specific.

Thermal Model of the AGR-5/6/7 Experiment with Offset Gas Gaps

Because of their high impact on calculated temperatures, the offset gas gaps between the graphite holder and capsule wall are evaluated for the thermal model of the Advanced Gas Reactor 5/6/7 (AGR-5/6/7) irradiation experiment. Fuel compact temperatures are a crucial factor in assessing the irradiation performance of tristructural isotropic (TRISO)-coated-particle fuel for use in high-temperature gas-cooled reactors. TRISO fuel irradiation performance is a core tenet of the U.S. Department of Energy’s Advanced Gas Reactor Fuel Development and Qualification Program, conducted in the Advanced Test Reactor at Idaho National Laboratory. Specifically, the irradiation experiments were intended to provide irradiation performance data to support fuel process development, qualify fuel for normal operating conditions, support the development of fuel performance models and codes, and provide irradiated fuel and materials for postirradiation examination and safety testing. The thermal model used to predict the fuel compact temperatures was a three-dimensional finite element model that was subject to uncertainty. The most dominant factor in the uncertainty pertaining to calculated fuel temperatures is the gas gap uncertainty, which is caused by the graphite holder nub-to-capsule wall clearance. In AGR-5/6/7 capsules, the graphite holders can be shifted away from being perfectly centered inside the stainless steel capsule walls. This is due to irradiation-induced graphite shrinkage or to insufficient nubs on the graphite holder leading to azimuthally varying gas gaps during irradiation. A method was developed to find the best offset magnitude and direction at the top and bottom of the graphite holders in Capsules 1 and 2, which experienced higher temperatures than originally predicted among the five AGR-5/6/7 axially dispersed capsules irradiated between 2018 and 2020. The differences between the calculated and the measured temperatures of thermocouples (TCs) placed in the graphite holder near the fuel compacts were used as the basis for the holder offset determination. The best-fit offset assumes that the root-mean-square error between the measured and calculated TC temperatures is a minimum value. Typical offsets in the range of 0.002 to 0.004 in. increase the fuel compact temperatures in the range of 100°C to 200°C when compared to the zero offset for Capsules 1 and 2. Additionally, because of irradiation-induced changes in the capsule geometries, the holder offsets change throughout the irradiation period.

Superfast Lombard response in free-flying, echolocating bats

Acoustic cues are crucial to communication, navigation, and foraging in many animals, which hence face the problem of detecting and discriminating these cues in fluctuating noise levels from natural or anthropogenic sources. Such auditory dynamics are perhaps most extreme for echolocating bats that navigate and hunt prey on the wing in darkness by listening for weak echo returns from their powerful calls in complex, self-generated umwelts.1,2 Due to high absorption of ultrasound in air and fast flight speeds, bats operate with short prey detection ranges and dynamic sensory volumes,3 leading us to hypothesize that bats employ superfast vocal-motor adjustments to rapidly changing sensory scenes. To test this hypothesis, we investigated the onset and offset times and magnitude of the Lombard response in free-flying echolocating greater mouse-eared bats exposed to onsets of intense constant or duty-cycled masking noise during a landing task. We found that the bats invoked a bandwidth-dependent Lombard response of 0.1-0.2 dB per dB increase in noise, with very short delay and relapse times of 20ms in response to onsets and termination of duty-cycled noise. In concert with the absence call time-locking to noise-free periods, these results show that free-flying bats exhibit a superfast, but hard-wired, vocal-motor response to increased noise levels. We posit that this reflex is mediated by simple closed-loop audio-motor feedback circuits that operate independently of wingbeat and respiration cycles to allow for rapid adjustments to the highly dynamic auditory scenes encountered by these small predators.

Effects of Deep Optic Nerve Head Structures on Bruch's Membrane Opening- Minimum Rim Width and Peripapillary Retinal Nerve Fiber Layer

PurposeTo explore the effects of deep optic nerve head (ONH) structures on Bruch's membrane opening (BMO)-minimum rim width (MRW) and peripapillary retinal nerve fiber layer thickness (pRNFLT) in healthy eyes. DesignProspective cross-sectional study MethodsTwo hundred five healthy eyes of 141 subjects (mean ± standard deviation of age and axial length (AXL): 46.9±10.0 years and 24.79±1.15 mm) were enrolled. Best fit multivariable linear mixed models identified factors associated with BMO-MRW and pRNFLT. Explanatory variables included age, sex, AXL, BMO and anterior scleral canal opening (ASCO) area and ovality, magnitude of BMO and ASCO shift, peripapillary choroidal thickness, lamina cribrosa (LC) parameters, prelaminar thickness and peripapillary scleral (PPS) angle. ResultsThinner BMO-MRW was associated with older age, smaller ASCO/BMO offset magnitude, larger BMO area, thinner prelaminar thickness, deeper LC, and thinner pRNFLT (p=0.011, <0.001, 0.004, <0.001, <0.001, <0.001 respectively). Thinner pRNFLT was associated with shorter AXL, smaller ASCO area, a more posteriorly bowed PPS, shallower LC and thinner BMO-MRW. (p=0.030, 0.002, 0.035, 0.012, <0.001 respectively) ConclusionsBMO-MRW and pRNFLT were influenced by several deep ONH structures such as BMO and ASCO position shift, BMO or ASCO area, prelaminar thickness, PPS bowing and LC depth in addition to patient characteristics such as age and AXL. The degree and/or direction of associations varied between deep ONH structures and BMO-MRW or pRNFLT. Despite both BMO-MRW and pRNFLT being surrogate parameters for RGC loss, a complex relationship with ONH deep-layer morphology was indicated.

Quantitative contribution of cryogenic vacuum extraction and radial water transport to xylem-source water deuterium offsets

The positions and magnitudes of deuterium offsets between bulk xylem and corresponding source waters are under debate and quantifying them is essential for isotope-based ecohydrological investigations. In this study, stable isotopes (δ2H, δ18O, and δ13C), iteration method, and rehydration experiments were combined to quantitatively determine the magnitude of cryogenic vacuum extraction (CVE)- and radial water transport (RWT)-induced deuterium offsets using one riparian tree species Salix babylonica L. A modified potential water source line (MPWL) was proposed to identify the total δ2H offsets between bulk xylem and source waters. The relationships between δ2H offsets induced by CVE or RWT and plant water content, leaf δ13C values, soil water content (SWC), and the depth to the water table (WTD) were investigated. Results showed that the bulk xylem waters in different tissue positions of S. babylonica showed −7.0 ‰ to −4.0 ‰ deuterium depletion relative to MPWL at four different sites (p < 0.01). The isotopic compositions of sap water coincided well with MPWL on the dual-isotope plot at the four sites. The CVE- and RWT-induced δ2H offsets accounted for 75.1 % and 24.9 % of the total δ2H offsets, respectively. The CVE-induced δ2H offsets were significantly negatively correlated with plant water content. In comparison, the RWT-induced δ2H offsets were negatively related to plant leaf δ13C values, trunk water content, and SWC, but positively correlated with WTD. This study provides a quantitative contribution of two major sources of deuterium offsets. The results provide critical insights into isotope-based plant water source identification and evapotranspiration partitioning.

Optical Coherence Tomographic Optic Nerve Head Morphology in Myopia III: The Exposed Neural Canal Region in Healthy Eyes—Implications for High Myopia

PurposeTo determine the prevalence and magnitude of OCT exposed neural canal (ENC), externally oblique choroidal border tissue (EOCBT), and exposed scleral flange (ESF) regions in 362 non-highly myopic (spherical equivalent -6.00 to 5.75 diopters) eyes of 362 healthy subjects. DesignCross-sectional study MethodsAfter OCT optic nerve head (ONH) imaging, Bruch's membrane opening (BMO), the anterior scleral canal opening (ASCO), and the scleral flange opening (SFO) were manually segmented. BMO, ASCO and SFO points were projected to BMO reference plane. The direction and magnitude of BMO/ASCO offset as well as the magnitude of ENC, EOCBT and ESF was calculated within 30° sectors relative to the Foveal-BMO axis. Hi-ESF eyes demonstrated an ESF ≥ 100 µms in at least one sector. Sectoral perineural canal choroidal thickness (pNC-CT) was measured and correlations between the magnitude of sectoral ESF and proportional pNC-CT were assessed. ResultsSeventy-three Hi-ESF (20.2%) and 289 Non-Hi-ESF eyes (79.8%) were identified. BMO/ASCO offset, as well as ENC, EOCBT and ESF prevalence and magnitude were greatest inferior temporally where pNC-CT was thinnest. Among Hi-ESF eyes, the magnitude of each ENC region correlated with BMO/ASCO offset magnitude and the sectors with the longest ESF correlated with the sectors with proportionally thinnest pNC-CT. ConclusionsONH BMO/ASCO offset, either as a cause or result of ONH neural canal remodeling, corresponds with the sectoral location of maximum ESF and minimum pNC-CT in non-highly myopic eyes. Longitudinal studies to characterize the development and clinical implications of ENC Hi-ESF regions in non-highly myopic and highly myopic eyes are indicated.

Magnetic Resonance Spectroscopy Spectral Registration Using Deep Learning.

Deep learning-based methods have been successfully applied to MRI image registration. However, there is a lack of deep learning-based registration methods for magnetic resonance spectroscopy (MRS) spectral registration (SR). To investigate a convolutional neural network-based SR (CNN-SR) approach for simultaneous frequency-and-phase correction (FPC) of single-voxel Meshcher-Garwood point-resolved spectroscopy (MEGA-PRESS) MRS data. Retrospective. Forty thousand simulated MEGA-PRESS datasets generated from FID Appliance (FID-A) were used and split into the following: 32,000/4000/4000 for training/validation/testing. A 101 MEGA-PRESS medial parietal lobe data retrieved from the Big GABA were used as the in vivo datasets. 3T, MEGA-PRESS. Evaluation of frequency and phase offsets mean absolute errors were performed for the simulation dataset. Evaluation of the choline interval variance was performed for the in vivo dataset. The magnitudes of the offsets introduced were -20 to 20 Hz and -90° to 90° and were uniformly distributed for the simulation dataset at different signal-to-noise ratio (SNR) levels. For the in vivo dataset, different additional magnitudes of offsets were introduced: small offsets (0-5 Hz; 0-20°), medium offsets (5-10 Hz; 20-45°), and large offsets (10-20 Hz; 45-90°). Two-tailed paired t-tests for model performances in the simulation and in vivo datasets were used and a P-value <0.05 was considered statistically significant. CNN-SR model was capable of correcting frequency offsets (0.014 ± 0.010 Hz at SNR 20 and 0.058 ± 0.050 Hz at SNR 2.5 with line broadening) and phase offsets (0.104 ± 0.076° at SNR 20 and 0.416 ± 0.317° at SNR 2.5 with line broadening). Using in vivo datasets, CNN-SR achieved the best performance without (0.000055 ± 0.000054) and with different magnitudes of additional frequency and phase offsets (i.e., 0.000062 ± 0.000068 at small, -0.000033 ± 0.000023 at medium, 0.000067 ± 0.000102 at large) applied. The proposed CNN-SR method is an efficient and accurate approach for simultaneous FPC of single-voxel MEGA-PRESS MRS data. 4 TECHNICAL EFFICACY: Stage 2.

Carbon Sequestration and Subsidence Reversal in the Sacramento-San Joaquin Delta and Suisun Bay: Management Opportunities for Climate Mitigation and Adaptation

The aquatic landscapes of the Sacramento–San Joaquin Delta (hereafter, the Delta) and Suisun Bay represent both a significant past and future soil carbon stock. Historical alterations of hydrologic flows have led to depletion of soil carbon stocks via emissions of carbon dioxide (CO2), and loss of elevation as a result of subsidence. Optimizing ecosystem hydrology in the Delta and Suisun Bay could both reduce and reverse subsidence while also providing significant opportunities for climate mitigation and adaptation. Emissions of greenhouse gases (GHGs)—notably CO2, methane (CH4 ), and nitrous oxide (N2O)—contribute to global warming at different rates and intensities, requiring GHG accounting and modeling to assess the relative benefits of management options. Decades of data collection, model building, and map development suggest that past and current management actions have both caused—and can mitigate—losses of soil carbon. We review here the magnitude of potential GHG offsets, management options that may be achievable, and trade-offs of carbon storage under different land management. Using a land-use/land-cover framework to assess these management options, we describe the potential of three interventions (impoundment to reverse subsidence, agricultural management, and tidal reintroduction and/or maintained connectivity), both in acreage and radiative balance to clarify their relative influence on the region’s GHG balance today and in relation to its millennial history. From floodplains to farming to floating aquatic vegetation, we find specific scalable strategies to manage hydrology that can alter regional GHG balance. Preservation of soil carbon stocks and restoration of net atmospheric CO2 fluxes into soils are the primary route to net negative emissions in the Delta and Suisun Bay, with CH4 emission management occurring in a supporting role. Over a 40-year horizon of climate-mitigation markets, the resilience of different aquatic habitats introduces the most uncertainty, from expected and unexpected hydrologic changes associated with land, ocean, and operational water flows.

A Non-Uniform Offset Algorithm for Milling Toolpath Generation Based on Boolean Operations

In milling, the advancement of CAM strategies has increased the need for tailored algorithms for semi-finished phase computation. In some cases (e.g., thin-wall milling), variable radial engagement of the tool during the toolpath is desired, leading to the need of non-uniform machining allowance on the component that could be achieved only with a non-uniform offset algorithm, i.e., offset where the distance to the initial contour varies along that input. This work presents a general algorithm for non-uniform offset of polyline curves. The approach is based on 2D polygons and Boolean union operation, following these steps: (i) projection segments are generated, (ii) polygons (trapezoids and circular sectors) are created, (iii) Boolean union of all the polygons is performed, (iv) boundary of interest is extracted. The proposed algorithm is able to handle both internal and external offset and is robust for complexity of both the polyline and variable offset magnitude along that line, as proven by several examples and two applications to thin-wall milling provided.

Conscious awareness of a visuo-proprioceptive mismatch: Effect on cross-sensory recalibration.

The brain estimates hand position using vision and position sense (proprioception). The relationship between visual and proprioceptive estimates is somewhat flexible: visual information about the index finger can be spatially displaced from proprioceptive information, resulting in cross-sensory recalibration of the visual and proprioceptive unimodal position estimates. According to the causal inference framework, recalibration occurs when the unimodal estimates are attributed to a common cause and integrated. If separate causes are perceived, then recalibration should be reduced. Here we assessed visuo-proprioceptive recalibration in response to a gradual visuo-proprioceptive mismatch at the left index fingertip. Experiment 1 asked how frequently a 70 mm mismatch is consciously perceived compared to when no mismatch is present, and whether awareness is linked to reduced visuo-proprioceptive recalibration, consistent with causal inference predictions. However, conscious offset awareness occurred rarely. Experiment 2 tested a larger displacement, 140 mm, and asked participants about their perception more frequently, including at 70 mm. Experiment 3 confirmed that participants were unbiased at estimating distances in the 2D virtual reality display. Results suggest that conscious awareness of the mismatch was indeed linked to reduced cross-sensory recalibration as predicted by the causal inference framework, but this was clear only at higher mismatch magnitudes (70–140 mm). At smaller offsets (up to 70 mm), conscious perception of an offset may not override unconscious belief in a common cause, perhaps because the perceived offset magnitude is in range of participants’ natural sensory biases. These findings highlight the interaction of conscious awareness with multisensory processes in hand perception.

Isotopic offsets between bulk plant water and its sources are larger in cool and wet environments

Abstract. Isotope-based approaches to study plant water sources rely on the assumption that root water uptake and within-plant water transport are non-fractionating processes. However, a growing number of studies have reported offsets between plant and source water stable isotope composition for a wide range of ecosystems. These isotopic offsets can result in the erroneous attribution of source water used by plants and potential overestimations of groundwater uptake by the vegetation. We conducted a global meta-analysis to quantify the magnitude of these plant source water isotopic offsets and explored whether their variability could be explained by either biotic or abiotic factors. Our database compiled 112 studies spanning arctic to tropical biomes that reported the dual water isotope composition (δ2H and δ18O) of plant (stem) and source water, including soil water (sampled following various methodologies and along a variable range of depths). We calculated plant source 2H offsets in two ways: a line conditioned excess (LC-excess) that describes the 2H deviation from the local meteoric water line and a soil water line conditioned excess (SW-excess) that describes the deviation from the soil water line, for each sampling campaign within each study. We tested for the effects of climate (air temperature and soil water content), soil class, and plant traits (growth form, leaf habit, wood density, and parenchyma fraction and mycorrhizal habit) on LC-excess and SW-excess. Globally, stem water was more depleted in 2H than in soil water (SW-excess &lt; 0) by 3.02±0.65 ‰ (P &lt; 0.05 according to estimates of our linear mixed model and weighted by sample size within studies). In 95 % of the cases where SW-excess was negative, LC-excess was negative, indicating that the uptake of water that had not undergone evaporative enrichment (such as groundwater) was unlikely to explain the observed soil–plant water isotopic offsets. Soil class and plant traits did not have any significant effect on SW-excess. SW-excess was more negative in cold and wet sites, whereas it was more positive in warm sites. The climatic effects on SW-excess suggest that methodological artefacts are unlikely to be the sole cause of observed isotopic offsets. Our results would imply that plant source water isotopic offsets may lead to inaccuracies when using the isotopic composition of bulk stem water as a proxy to infer plant water sources.

Tomographic Imaging and Localization of Nanoparticles in Tissue Using Surface-Enhanced Spatially Offset Raman Spectroscopy.

A fundamental question crucial to surface-enhanced spatially offset Raman spectroscopy (SESORS) imaging and implementing it in a clinical setting for in vivo diagnostic purposes is whether a SESORS image can be used to determine the exact location of an object within tissue? To address this question, multiple experimental factors pertaining to the optical setup in imaging experiments using an in-house-built point-collection-based spatially offset Raman spectroscopy (SORS) system were investigated to determine those critical to the three-dimensional (3D) positioning capability of SESORS. Here, we report the effects of the spatial offset magnitude and geometry on locating nanoparticles (NPs) mixed with silica powder as an imaging target through tissue and outline experimental techniques to allow for the correct interpretation of SESORS images to ascertain the correct location of NPs in the two-dimensional x, y-imaging plane at depth. More specifically, the effect of “linear offset-induced image drag” is presented, which refers to a spatial distortion in SESORS images caused by the magnitude and direction of the linear offset and highlight the need for an annular SORS collection geometry during imaging to neutralize these asymmetric effects. Additionally, building on these principles, the concept of “ratiometric SESORS imaging” is introduced for the location of buried inclusions in three dimensions. Together these principles are vital in developing a methodology for the location of surface-enhanced Raman scattering-active inclusions in three dimensions. This approach utilizes the relationship between the magnitude of the spatial offset, the probed depth, and ratiometric analysis of the NP and tissue Raman intensities to ultimately image and spatially discriminate between two distinct NP flavors buried at different depths within a 3D model for the first time. This research demonstrates how to accurately identify multiple objects at depth in tissue and their location using SESORS which addresses a key capability in moving SESORS closer to use in biomedical applications.

Geomorphic Dating of Across‐Fault Gully Incision Reveals Time‐Invariant Late Quaternary Slip‐Rates at the Eastern Termination of the Altyn Tagh Fault

AbstractInterpretation of fault slip‐rates inferred from tectonically offset fluvial landforms is often limited by uncertainties associated with difficulties to explicitly date fluvial incision across the fault. Here, we employed morphology‐based modeling to ameliorate this universal dating limitation for gullies that were differentially offset in a sinistral sense across the Altyn Tagh Fault near its eastern termination at ∼97°E. Using a stream‐power erosion model with locally calibrated coefficients we calculated across‐fault gully incision ages that decrease with offset magnitude, are up to threefold younger than the age of the terrace they incised and all‐together point toward time‐invariant slip. Luminescence dating of offset alluvial terraces at the same site suggests constant sinistral slip at 0.5 ± 0.1 mm/yr since 52 ± 4 ka. Our results suggest that the most juvenile phase of northeastward Pleistocene expansion of the Tibetan Plateau into previously stable parts of central Asia is marked by constant late Quaternary deformation rates.

A model-based strategy for quadruped running with differentiated fore- and hind-leg morphologies

This article introduces a model-based strategy for a quadruped robot with differentiated fore- and hind-leg ground reaction force patterns to generate animal-like running behavior. The proposed model comprises a rigid body and two eccentric spring-loaded inverted pendulum (eSLIP) legs with dampers. The eSLIP model extends the traditional SLIP model by adding a bar to offset the spring direction. The proposed two-leg eSLIP (TL-eSLIP) model’s fore- and hind legs were designed to have the same offset magnitude but in opposite offset directions, producing different braking and thrusting force patterns. The TL-eSLIP model’s reference leg trajectories were designed based on the fixed-point motion of the eSLIP model. Additionally, the legs were clock torque-controlled to modulate leg motion and stabilize the model to follow its natural dynamics. The model’s equations for motion were derived, and the model’s dynamic behavior was simulated and analyzed. The simulation results indicate that the model with leg offsets and in either trotting or pronking has differentiated leg force patterns, and it is more stable and has larger basins of attraction than the model without leg offsets. A quadruped robot was built for experimental validation. The experimental results demonstrate that the robot with differentiated legs ran with differentiated ground reaction force patterns and ran more stably than another robot with the same leg morphology.

A New Adaptive Absolute Method for Homogenizing GNSS‐Derived Precipitable Water Vapor Time Series

AbstractThe inhomogeneities, the so‐called changepoints, inevitably occur in the precipitable water vapor (PWV) time series derived from Global Navigation Satellite Systems (GNSS‐PWV). Currently, the two predominant types of homogenization methods, that is, absolute and relative methods, are limited in the poor performance and dependency on reference time series. In this study, a new absolute approach named adaptive absolute homogenization test (AAHT) by combining Seasonal‐Trend decomposition based on LOESS (STL) and Penalized Maximal F‐test to account for the red noise (PMFred) is proposed. The performance of the new approach was validated using Monte Carlo simulations. Results showed the success rate and false alarm rate were better than 74.9% and 12.2%; the detection accuracy of the changepoint epochs and the offset magnitudes were 8.0 days and 0.153 mm. AAHT was also applied to homogenizing the real GNSS‐PWV time series over 91 International GNSS Service stations, from which 63 time series were identified as inhomogeneous containing 126 changepoints. Based on a comparison with the PWV time series from the fifth‐generation European center for medium‐range weather forecasts (ECMWF) reanalysis (ERA5), 43 changepoints were connected to climatic drivers, leaving 83 artificial changepoints at 48 stations. The offset magnitudes at these artificial changepoints were estimated and corrected in the inhomogeneous time series. The long‐term trends of those homogenized time series were compared with that of the PWV time series derived from ERA5 data sets (ERA‐PWV) and the correlation coefficient between the two sets of trends was 0.75, which was significantly larger than 0.23 before homogenization.

Does tall vegetation warm or cool the ground surface? Constraining the ground thermal impacts of upright vegetation in northern environments

Increased upright vegetation growth (i.e. trees and shrubs) in northern environments can profoundly impact ground surface thermal conditions through winter warming (e.g. enhanced snow trapping) and summer cooling (e.g. increased shading). The debate over these opposite effects emphasizes the need to better constrain net temperature impacts of upright vegetation on soils in northern environments. We generate a series of simulations with a widely-used permafrost model to partition the absolute warming and cooling impacts of upright vegetation on ground surface temperatures for a variety of shading scenarios, climates and surficial materials types (i.e. bedrock, mineral and organic soils). These scenarios simulate annual temperature differences between the air and ground surface caused by upright vegetation to provide likely ranges for the net effects induced by vegetation. These simulations showed that ground surface temperature warming in the winter mostly overwhelmed ground surface cooling in the thawing season even when simulations included extreme shading effects. Constraining the simulations to current best estimates of the possible summer cooling impact of vegetation yielded a dominant winter warming signal for most snow depths and climate types. Differences in the magnitude of air-surface temperature offsets between sites underlain by bedrock, mineral and organic soil highlights the importance of considering differences in unfrozen moisture content in areas where the ground freezes and thaws seasonally. The results of this study suggest that the net ground surface temperature impacts of increased snow trapping by vegetation will far exceed cooling caused by enhanced shading following increases in tall vegetation in most northern environments.

Characteristics of Copayment Offsets for Prescription Drugs in the United States

Despite ongoing debate regarding the high prices that patients pay for prescription drugs, to our knowledge, little is known regarding the use of coupons, vouchers, and other types of copayment "offsets" that reduce patients' out-of-pocket drug spending. Although offsets reduce patients' immediate cost burden, they may encourage the use of higher-cost products and diminish health insurers' ability to optimize pharmaceutical value. To examine the drugs most commonly covered by offsets, the percentage of out-of-pocket costs covered by offsets, and the characteristics of patients using offsets for retail pharmacy transactions in the United States in 2017 through 2019. A retrospective cohort analysis was conducted of a 5% nationally random sample of anonymized pharmacy claims from IQVIA's Formulary Impact Analyzer, which captures more than 60% of all US pharmacy transactions. This analysis focused on 631 249 individuals who used at least 1 offset between October 1, 2017, and September 30, 2019. Offset source, types of drugs covered by offsets, offset dollar value and percentage of out-of-pocket payment covered, and county characteristics of offset recipients. The 631 249 individuals in the study (361 855 female participants [57.3%]; mean [SD] age, 45.7 [18.6] years) had approximately 33 million prescription fills, of which 12.8% had an offset used. Of these, 50.2% originated from a pharmaceutical manufacturer, 47.2% originated from a pharmacy or pharmacy benefit manager (PBM), and 2.6% originated from a state assistance program. A total of 80.0% of manufacturer-sponsored offsets were concentrated among 6.2% of unique products, and 79.9% of pharmacy-PBM offsets were concentrated among 4.9% of unique products. Most manufacturer offsets (88.2%) were for branded products, while most pharmacy-PBM offsets were for generic products (90.5%). The median manufacturer offset was $51.00, covering 87.1% of out-of-pocket costs; the median pharmacy-PBM offset was $16.30, covering 39.3% of out-of-pocket costs. There was no meaningful association between offset magnitude and county-level income, health insurance coverage, or race/ethnicity. In this analysis of patient-level pharmacy claims from 2017 to 2019, approximately half of all offsets involved pharmacy-PBM contractual arrangements, and half were offered by manufacturers. All offsets were associated with a significant reduction in patients' out-of-pocket costs, were highly concentrated among a few drugs, and were generally not more generous among individuals in counties with lower income or larger Black or uninsured populations.

Distribution of Pupil Offset and Angle Kappa in a Refractive Surgery Preoperative Population of 750 Myopic, Emmetropic, and Hyperopic Eyes.

To report the distribution of pupil offset and angle kappa in 750 myopic, emmetropic, and hyperopic eyes presenting for refractive surgery. A retrospective study included 750 consecutive eyes screened for corneal refractive surgery between January 2006 and February 2013. The eyes were divided into three equal groups based on manifest refraction spherical equivalent (SEQ): emmetropic group between -0.25 and +0.50 diopters (D) and cylinder up to 1.00 D, myopic group greater than -0.50 D, and hyperopic group greater than +0.50 D. Angle kappa was measured with the Orbscan II software (Bausch & Lomb, Inc) and pupil offset defined as the distance at the corneal plane between the corneal vertex and the pupil center. Correlations with SEQ, cylinder, scotopic pupil diameter, average keratometry, and age were performed. All results are reported for myopic, emmetropic, and hyperopic groups, respectively. Mean SEQ was -4.84 ± 2.89 D (range: -0.88 to -14.00 D), +0.21 ± 0.23 D (range: -0.25 to +0.50 D), and +2.44 ± 1.58 D (range: +0.63 to +7.75 D). Mean pupil offset magnitude was 0.27 ± 0.14 mm (range: 0.00 to 0.68 mm), 0.34 ± 0.14 mm (range: 0.02 to 0.78 mm), and 0.39 ± 0.13 mm (range: 0.07 to 0.75 mm). Mean pupil offset X-component was -0.18 ± 0.18, -0.28 ± 0.16, and -0.34 ± 0.15 mm (temporally displaced from the corneal vertex). Mean pupil offset Y-component was 0.06 ± 0.15, 0.03 ± 0.16, and 0.01 ± 0.16 mm (superiorly displaced from the corneal vertex). Multivariate linear regression for pupil offset magnitude found statistically significant variables were SEQ, cylinder, scotopic pupil diameter, and average keratometry. For pupil offset X-component, significant variables were SEQ, cylinder, and scotopic pupil diameter. For pupil offset Y-component, significant variables were SEQ and scotopic pupil diameter. Mean angle kappa was 5.28 ± 1.49°, 6.14 ± 1.44°, and 5.77 ± 1.29°. Contrary to common belief, a pupil offset is present in the vast majority of eyes regardless of refractive error, with the mean temporal offset of at least 0.18 mm. Confirming previous studies, the largest pupil offset was found in the hyperopic group. However, there was also a wide range of pupil offset in myopic and emmetropic eyes. Correlations with SEQ and keratometry support the theory that pupil offset is also correlated with axial length. [J Refract Surg. 2021;37(1):49-58.].

Effects of sampling time interval on the image offsets of the observed points for Moon-based earth observations

ABSTRACT Due to the almost hemispheric observational scope of the Moon-based Earth observations, the effects of sampling time interval on the image offsets of the observed points are fundamentally different from the cases of traditional satellite-based platforms. Sampling time intervals will affect the offsets in the full-disc image, while the magnitude of the image offsets is dependent on the spatial resolution. Hence, their relationships merit further investigation. To this end, a novel method to determine the image coordinates based on radius-angle pair expression is proposed. The offsets of the observed points between two adjacent samplings can be calculated and the effects of the sampling time interval on the offsets can be analysed. We found that the magnitude of the image offsets in the x-axis direction is approximately two times larger than that in y-axis direction under the same sampling time interval and the effects of the sampling time interval is related to the observed point’s latitude. Further, based on the fact that the maximum offsets occur at the Earth’s equator, the detailed calculation of the shortest sampling time interval taken to exceed 1-pixel offset corresponding to different spatial resolutions is carried out. The results described herein can provide guidance for designing sensors for Moon-based Earth observations.

Spatially offset black holes in the Horizon-AGN simulation and comparison to observations

ABSTRACT We study the displacements between the centres of galaxies and their supermassive black holes (BHs) in the cosmological hydrodynamical simulation Horizon-AGN, and in a variety of observations from the literature. The BHs in Horizon-AGN feel a subgrid dynamical friction force, sourced by the surrounding gas, which prevents recoiling BHs being ejected from the galaxy. We find that (i) the fraction of spatially offset BHs increases with cosmic time, (ii) BHs live on prograde orbits in the plane of the galaxy with an orbital radius that decays with time but stalls near z = 0, and (iii) the magnitudes of offsets from the galaxy centres are substantially larger in the simulation than in observations. We attribute the stalling of the infall and excessive offset magnitudes to the fact that dynamical friction from stars and dark matter is not modelled in the simulation, and hence provide a way to improve the BH dynamics of future simulations.