Field Of Regard Research Articles

Bias characterization of CrIS radiances at 399 selected channels with respect to NWP model simulations

The Cross-track Infrared Sounder (CrIS) on board the Suomi National Polar-Orbiting Partnership (S-NPP) satellite is a hyperspectral Fourier Transform Spectrometer. In this study, biases of the 399 channels used in numerical weather prediction applications are characterized based on the differences between CrIS observations and model simulations in clear-sky conditions over ocean. The Visible Infrared Imaging Radiometer Suite (VIIRS) cloud mask is used for selecting CrIS clear-sky data. The global mean biases are within ±1K for most channels (more than 390). Biases for the channels not affected by trace gases other than water vapor in long-wave infrared (LWIR), middle-wave infrared (MWIR) and short-wave infrared (SWIR) bands vary from about −0.5 to 0.3K, −0.2 to 0.8K, and −0.1 to 0.9K, respectively. The scan-angle variations of biases are less than ±0.4K for all channels. The MWIR sounding channels have larger biases in middle and high latitudes than the tropics, which might be associated with latitudinal differences of water vapor variability. The SWIR CO2 channels are affected by nonlocal thermodynamic equilibrium (NLTE) in the upper stratosphere and the window channels could be affected by the sun glint effect, both of which are considered in model simulations. Biases of the NLTE affected channels during daytime are found to be 0.5–1K higher than nighttime. The SWIR window channels have colder biases at Field of Regards (FORs) 6–15 than the other scan positions due to the sun glint effect.

Entanglement and Pancharatnam Phase of a Four-Level Atom in Coherent States Within Generalized Heisenberg Algebra

We consider a four-level atom (FLA) interacting with a field mode that is initially in a coherent state associated with a generalized Heisenberg algebra (CSGHA). The dynamical behavior of quantum entropy, the Pancharatnam phase, and the Mandel parameter are investigated. The statistical and nonclassical properties of the field in regard to its CSGHA are discussed through the evolution of the Mandel parameter, and the effects of the initial atomic state position and time-dependent coupling given in terms of atomic speed and acceleration are examined. The results show that the CSGHA strength and time-dependent coupling based on the atomic speed and acceleration have the potential to affect the time evolution of the entanglement, the Pancharatnam phase, and the Mandel parameter.

Beam steering uncertainty analysis for Risley prisms based on Monte Carlo simulation

The Risley-prism system is applied in imaging LADAR to achieve precision directing of laser beams. The image quality of LADAR is affected deeply by the laser beam steering quality of Risley prisms. The ray-tracing method was used to predict the pointing error. The beam steering uncertainty of Risley prisms was investigated through Monte Carlo simulation under the effects of rotation axis jitter and prism rotation error. Case examples were given to elucidate the probability distribution of pointing error. Furthermore, the effect of scan pattern on the beam steering uncertainty was also studied. It is found that the demand for the bearing rotational accuracy of the second prism is much more stringent than that of the first prism. Under the effect of rotation axis jitter, the pointing uncertainty in the field of regard is related to the altitude angle of the emerging beam, but it has no relationship with the azimuth angle. The beam steering uncertainty will be affected by the original phase if the scan pattern is a circle. The proposed method can be used to estimate the beam steering uncertainty of Risley prisms, and the conclusions will be helpful in the design and manufacture of this system.

Neurodiagnostic Laboratory Accreditation: An Overview

The development of credentials for technologists has had a measurable impact on the neurodiagnostic field in regards to standardization, quality control, and salaries (Careers in Diagnostics, ASET ...

Potential of a geostationary geoCARB mission to estimate surface emissions of CO<sub>2</sub>, CH<sub>4</sub> and CO in a polluted urban environment: case study Shanghai

Abstract. This paper describes a numerical experiment to test the ability of the proposed geoCARB satellite to estimate emissions of trace gases (CO2, CH4 and CO) in the polluted urban environment of Shanghai. The meteorology over Shanghai is simulated with the Weather Research and Forecasting (WRF) model for a 9-day period in August 2010. The meteorology includes water and ice clouds. The chemistry version of WRF (WRF-Chem V3.6.1) is used to predict the chemical composition, mass density and number density of aerosol species. Spectra in the bands measured by geoCARB are calculated, including the effects of polarisation and multiple scattering of radiation by clouds, aerosols and molecules. Instrument noise is added, and column-averaged trace-gas mole fractions are estimated from the noisy spectra using an algorithm based on that for the Greenhouse Gases Observing Satellite (GOSAT) and the Orbiting Carbon Observatory-2 (OCO-2) but adapted to geoCARB. As expected, the high aerosol loadings are challenging. However, when the retrieval algorithm is provided with regionally adjusted aerosol optical properties, as might be determined from observations of dark targets within the field of regard, the accuracies of retrieved concentrations are comparable to those reported earlier for geoCARB. Statistics of the errors in the retrieved column-averaged concentrations are used to predict the reduction in uncertainty of surface emissions possible with remotely sensed data.

Impacts of field of view configuration of Cross-track Infrared Sounder on clear-sky observations.

Hyperspectral infrared radiance measurements from satellite sensors contain valuable information on atmospheric temperature and humidity profiles and greenhouse gases, and therefore are directly assimilated into numerical weather prediction (NWP) models as inputs for weather forecasting. However, data assimilations in current operational NWP models still mainly rely on cloud-free observations due to the challenge of simulating cloud-contaminated radiances when using hyperspectral radiances. The limited spatial coverage of the 3×3 field of views (FOVs) in one field of regard (FOR) (i.e., spatial gap among FOVs) as well as relatively large footprint size (14 km) in current Cross-track Infrared Sounder (CrIS) instruments limits the amount of clear-sky observations. This study explores the potential impacts of future CrIS FOV configuration (including FOV size and spatial coverage) on the amount of clear-sky observations by simulation experiments. The radiance measurements and cloud mask products (VCM) from the Visible Infrared Imager Radiometer Suite (VIIRS) are used to simulate CrIS clear-sky observation under different FOV configurations. The results indicate that, given the same FOV coverage (e.g., 3×3), the percentage of clear-sky FOVs and the percentage of clear-sky FORs (that contain at least one clear-sky FOV) both increase as the FOV size decreases. In particular, if the CrIS FOV size were reduced from 14 km to 7 km, the percentage of clear-sky FOVs increases from 9.02% to 13.51% and the percentage of clear-sky FORs increases from 18.24% to 27.51%. Given the same FOV size but with increasing FOV coverage in each FOR, the clear-sky FOV observations increases proportionally with the increasing sampling FOVs. Both reducing FOV size and increasing FOV coverage can result in more clear-sky FORs, which benefit data utilization of NWP data assimilation.

Human field of regard, field of view, and attention bias

Background and objectiveHuman field of regard (FOR) is an important concept that should be considered along with field of view (FOV) for people with/without handicaps, but previous studies have neglected this aspect of human perception. In the current study, we suggest and test a new virtual reality (VR) software with which to evaluate individual's detection abilities in the human FOR. MethodsWe conducted measurements of human FOV, FOR, and FOR with visual cue (FOR-cue), and we evaluated healthy adults' responses in a first experiment. Participants were asked to detect targets on a head-mounted display (HMD) as quickly as possible in three conditions: (a) FOV: the head rotation doesn't change the view of the screen in the HMD; (b) FOR: the head rotation changes the view of the screen in the HMD; and (c) FOR-cue: same with the FOR condition but an endogenous visual cue indicating the direction of stimulus. To address the need to increase the number of trials in the FOR condition, we also conducted a second experiment with new samples and four times of trial numbers. ResultsThe participants' detection time results indicated that the FOV condition was faster than the FOR-cue and FOR conditions, and the FOR-cue was faster than the FOR condition. Interestingly, we found a unique characteristic in the FOR conditions that did not exist in the FOV condition: The target responses were faster for the left side than the right side. The results of the second experiment were consistent with the first, and head motion trajectory analysis showed that participants had more movement toward the left side than the right side in the early parts of each trial. ConclusionsIn this study, we suggested a new virtual reality (VR) evaluation technique and measured the human searching pattern in the FOR condition. We found a unique left-side attention bias in the FOR condition, and discussed implication of these results and potential attention bias factors. We believe this work is an important foundation for interactive 3D UI design, and we hope it will help people who have FOR handicaps.

Conformal dome aberration correction by designing the inner surface

The ray transmission models of optical domes were established, and the characteristics of the rays while passing through a hemispherical dome and a conformal dome were comparatively analysed. Acquiring the minimum deviated angles from the inner surface of the conformal dome was then determined to be the designing goal for reducing the dynamic aberrations. Based on this, the inner surface of the conformal dome was optimized and thus, the dynamic aberrations were reduced. Finally, a completely cooled conformal optical system was designed. The results show that the optical system have produced good imaging quality within all the fields of regard, which further illustrates that designing the inner surface of a conformal dome is an effective method for aberration correction.

The Effects of Theory of Mind Training on the False Belief Understanding of Deaf and Hard-of-Hearing Students in Prekindergarten and Kindergarten.

Data from a growing number of research studies indicate that children with hearing loss are delayed in Theory of Mind (ToM) development when compared to their typically developing, hearing peers. While other researchers have studied the developmental trajectories of ToM in school-age students who are deaf, a limited number have addressed the need for interventions for this population. The present study extends the current research on ToM interventions to the Prekindergarten and Kindergarten levels. This study used a single-case multiple baseline design to examine the effects of a ToM intervention on participants' false belief understanding as well as outcomes on a near generalization measure and a far generalization measure. A ToM thought bubble intervention (i.e., a visual representation of what people are thinking) developed by Wellman and Peterson (2013 Deafness, thought bubbles, and theory-of-mind development. Developmental Psychology, 49, 2357-2367) was modified in key areas. Results from the Single-Case Design portion of the study indicate a functional, or causal, relation between the ToM intervention and the participants' acquisition of the targeted skills in each stage although progress was not uniform. Results from the pre-post assessments indicate that the children did make progress up the scale. These results inform the field in regard to the efficacy and feasibility of a ToM intervention for young deaf children.

Efficient multibeam large-angle nonmechanical laser beam steering from computer-generated holograms rendered on a liquid crystal spatial light modulator.

Multibeam large-angle beam steering is demonstrated in the visible spectral region by imprinting computer-generated holographic Fresnel zone plates on a liquid crystal spatial light modulator (SLM) configured as the first element of a telescope. The position and intensity of each beam are controlled independently. The laser beam is steered over a ±37° field of regard, with the power in the beam at 37° being greater than 50% of the on-axis power. The power delivered on axis for a single beam was 48% of the power incident on the SLM. The beam profile remained Gaussian over the full steering range, and the on-axis beam divergence is 2.1mrad.

E. sveikatos intervencijų esant stresiniams sutrikimams perspektyvos: kritinė apžvalga

The aim of this paper is to review the current status of e-health interventions and discuss the main controversies and issues related to e-health definitions, forms of IT-based interventions, limitations and advantages, as well as directions for future research. Alongside the benefits that rapid development of ITbased psychosocial interventions bring to the mental health care system, they also bring challenges for patients, professionals, and researchers in the field in regard to methodology and terminology. There is also a huge variety of different forms of IT-based interventions. The popularity of these interventions is growing because of their convenience, cost-effectiveness, fewer stigmas attached to them, and other benefits. On the other hand, there are legal, ethical, confidentiality, and other questions that need to be considered. IT-based interventions for stress-related disorders share all of these difficulties. However, we also need to look at problems that come from dealing with a specific disorder. Research of IT-based interventions for stressrelated disorders confirms their effectiveness but also shows that their effectiveness can depend on the user’s and intervention’s qualities, hence more research on these variables is needed.

Book Review: Aullón de Haro, P. (ed.) (2015). Historiografía y Teoría de la Historia del Pensamiento, la Literatura y el Arte. Madrid: Dykinson.

Book Review: Aullón de Haro, P. (ed.) (2015). Historiografía y Teoría de la Historia del Pensamiento, la Literatura y el Arte. Madrid: Dykinson.

Emerging therapeutic targets in esophageal adenocarcinoma.

The incidence of gastro-esophageal disease and associated rate of esophageal adenocarcinoma (EAC) is rising at an exponential rate in the United States. However, research targeting EAC is lagging behind, and much research is needed in the field to identify ways to diagnose EAC early as well as to improve the rate of pathologic complete response (pCR) to systemic therapies. Esophagectomy with subsequent reconstruction is known to be a morbid procedure that significantly impacts a patient's quality of life. If indeed the pCR rate of patients can be improved and those patients destined to be pCR can be identified ahead of time, they may be able to avoid this life-altering procedure. While cancer-specific biological pathways have been thoroughly investigated in other solid malignancies, much remains unexplored in EAC. In this review, we will highlight some of the latest research in the field in regards with EAC, along with new therapeutic targets that are currently being explored. After reviewing conventional treatment and current changes in medical therapy for EAC, we will focus on unchartered grounds such as cancer stem cells, genetics and epigenetics, immunotherapy, and chemoradio-resistant pathways as we simultaneously propose some investigational possibilities that could be applicable to EAC.

A Compact Top-View Conformal Optical System Based on a Single Rotating Cylindrical Lens with Wide Field of Regard

A new compact conformal dome optical system was established, and the aberration characteristics of the dome were investigated using Zernike aberration theory. The aberrations induced by the dome at different fields of regard (FORs) from 30° to 100° were effectively balanced by a rotating cylindrical lens. This kind of optical system can be widely used in top-view optical searching devices. A design method was introduced and the optimization results analyzed in detail. The results showed that the Zernike aberrations produced by the conformal dome were decreased dramatically. Also, a complete conformal optical system was designed, to further illustrate the aberration correction effect of the rotating cylindrical lens. Using a cylindrical lens not only provided a large FOR, but also simplified enormously the structure of the conformal optical system.

Research of aberration characteristics of conicoidal conformal optical domes

Most conformal optical system designs concentrate on the researches of ellipdoidal domes. However, ellipsoidal domes are not the best ones which possess excellent aerodynamic performance among conicoidal conformal domes. This paper investigates the aberration characteristics of conicoidal conformal domes. For the purpose of the study, different types of infrared conformal domes, including ellipsoidal domes, parabolic domes and hyperbolic domes, with the common fineness ratio of 1.0 and an index of refraction of 2.25 are modeled by mathematical computation. To investigate the dynamic characteristics of the on-axis aberrations, the curves of third order fringe Zernike polynomials of the domes across field of regard are obtained by decomposing the incident wavefront at the exit pupil. The Zernike aberrations across field of view are also achieved to investigate the varying characteristics of off-axis aberrations. To find the similarities and difference between spherical domes and conformal domes at both field of regard and field of view, also make the foundation for optical design, spherical domes and defocused spherical domes are modeled for reference researches. The changing rules and the features of the aberrations among different types of conicoidal conformal domes are drawn as conclusions at the end of the paper.

Cloud‐induced uncertainties in AIRS and ECMWF temperature and specific humidity

AbstractThe uncertainties of the Atmospheric Infrared Sounder (AIRS) Level 2 version 6 specific humidity (q) and temperature (T) retrievals are quantified as functions of cloud types by comparison against Integrated Global Radiosonde Archive radiosonde measurements. The cloud types contained in an AIRS/Advanced Microwave Sounding Unit footprint are identified by collocated Moderate Resolution Imaging Spectroradiometer retrieved cloud optical depth (COD) and cloud top pressure. We also report results of similar validation of q and T from European Centre for Medium‐Range Weather Forecasts (ECMWF) forecasts (EC) and retrievals from the AIRS Neural Network (NNW), which are used as the initial state for AIRS V6 physical retrievals. Differences caused by the variation in the measurement locations and times are estimated using EC, and all the comparisons of data sets against radiosonde measurements are corrected by these estimated differences. We report in detail the validation results for AIRS GOOD quality control, which is used for the AIRS Level 3 climate products. AIRS GOOD quality q reduces the dry biases inherited from the NNW in the middle troposphere under thin clouds but enhances dry biases in thick clouds throughout the troposphere (reaching −30% at 850 hPa near deep convective clouds), likely because the information contained in AIRS retrievals is obtained in cloud‐cleared areas or above clouds within the field of regard. EC has small moist biases (~5–10%), which are within the uncertainty of radiosonde measurements, in thin and high clouds. Temperature biases of all data are within ±1 K at altitudes above the 700 hPa level but increase with decreasing altitude. Cloud‐cleared retrievals lead to large AIRS cold biases (reaching about −2 K) in the lower troposphere for large COD, enhancing the cold biases inherited from the NNW. Consequently, AIRS GOOD quality T root‐mean‐squared errors (RMSEs) are slightly smaller than the NNW errors in thin clouds (1.5–2.5 K) but slightly larger than the NNW errors for thick COD (reaching 3.5 K near the surface). The AIRS BEST quality control retains retrievals with uncertainties closer to those of the NNW. The AIRS error estimates reported in the L2 product tend to underestimate the precision (RMSE) implied by comparisons to the radiosonde measurements and do not reflect the observed cloud dependency of uncertainties.

Arrhythmogenic mechanisms in ryanodine receptor channelopathies.

Ryanodine receptors (RyRs) are the calcium release channels of sarcoplasmic reticulum (SR) that provide the majority of cal-cium ions (Ca2+) necessary to induce contraction of cardiac and skeletal muscle cells. In their intracellular environment, RyR channels are regulated by a variety of cytosolic and luminal factors so that their output signal (Ca2+) induces finely-graded cell contraction without igniting cellular processes that may lead to aberrant electrical activity (ventricular arrhythmias) or cellular remodeling. The importance of RyR dysfunction has been recently highlighted with the demonstration that point mutations in RYR2, the gene encoding for the cardiac isoform of the RyR (RyR2), are associated with catecholaminergic polymorphic ventricular tachycardia (CPVT), an arrhythmogenic syndrome characterized by the development of adrenergically-mediated ventricular tachycardia in individuals with an apparently normal heart. Here we summarize the state of the field in regards to the main arrhythmogenic mechanisms triggered by RyR2 channels harboring mutations linked to CPVT. Most CPVT mutations characterized to date endow RyR2 channels with a gain of function, resulting in hyperactive channels that release Ca2+ spontaneously, especially during diastole. The spontaneous Ca2+ release is extruded by the electrogenic Na+/Ca2+ exchanger, which depolarizes the external membrane (delayed afterdepolarization or DAD) and may trigger untimely action potentials. However, a rare set of CPVT mutations yield RyR2 channels that are intrinsically hypo-active and hypo-responsive to stimuli, and it is unclear whether these channels release Ca2+ spontaneously during diastole. We discuss novel cellular mechanisms that appear more suitable to explain ventricular arrhythmias due to RyR2 loss-of-function mutations.

Synergistic use of Imager Window observations for Cloud Clearing of Sounder Observation for INSAT-3D

Abstract. The retrieval of atmospheric temperature and water vapor profiles from infrared Sounder are severely limited by the presence of cloud. Therefore, retrieval from infrared sounding observations is performed only over clear-sky atmospheric conditions. The probability of finding a clear-sky pixel at spatial resolution of 10 km is found to be very small globally. This study presents a quantitative analysis of the clear-sky probability that is carried out for different months over the Indian region for INSAT-3D Sounder. The probability of a clear-sky is found to be ~7 % for the field of view of 10 km corresponding to the INSAT-3D Sounder. This statistical analysis is established using MODIS cloud mask having 95 % confidence level at 1 km resolution spread in the region between 50E–110E and 30S–30N. This necessitates cloud clearing to remove the effect of partial clouds in the Sounder FOV to provide a clear-sky equivalent sounding retrieval. Various methods were explored to derive the cloud-cleared radiances using supplementary information such as high resolution infrared or microwave observations. This study presents an effort to use the existing traditional method to derive optimal cloudcleared radiances for INSAT-3D Sounder, by estimating the fractional cloud cover using collocated high resolution INSAT-3D Imager window channel observation. The final Sounder cloud-cleared radiances have been validated with the operational AIRS L2 cloud-cleared radiance products. Nevertheless, the statistical analysis of clear-sky probability over Indian region also provides a significant insight towards the dependency of spatial resolution and the considerable field-of-regard (FOR) in obtaining the clear-sky area in the satellite observations. This, in a way, necessitates the cloud-clearing for coarser resolution sensors and at the same time, states the benefits of using very high resolution sensors. It has been observed that FOV of 1km and by choosing a reasonably good FOR can eliminate the cloudy-sky hindrances by increasing the probability of clear-sky from 5 % to 50 %.

Pointing error analysis of Risley-prism-based beam steering system.

Based on the vector form Snell's law, ray tracing is performed to quantify the pointing errors of Risley-prism-based beam steering systems, induced by component errors, prism orientation errors, and assembly errors. Case examples are given to elucidate the pointing error distributions in the field of regard and evaluate the allowances of the error sources for a given pointing accuracy. It is found that the assembly errors of the second prism will result in more remarkable pointing errors in contrast with the first one. The pointing errors induced by prism tilt depend on the tilt direction. The allowances of bearing tilt and prism tilt are almost identical if the same pointing accuracy is planned. All conclusions can provide a theoretical foundation for practical works.

Feasibility of Training Athletes for High-Pressure Situations Using Virtual Reality

Virtual reality (VR) has been successfully applied to a broad range of training domains; however, to date there is little research investigating its benefits for sport psychology training. We hypothesized that using high-fidelity VR systems to display realistic 3D sport environments could trigger anxiety, allowing resilience-training systems to prepare athletes for real-world, highpressure situations. In this work we investigated the feasibility and usefulness of using VR for sport psychology training. We developed a virtual soccer goalkeeping application for the Virginia Tech Visionarium VisCube (a CAVE-like display system), in which users defend against simulated penalty kicks using their own bodies. Using the application, we ran a controlled, within-subjects experiment with three independent variables: known anxiety triggers, field of regard, and simulation fidelity. The results demonstrate that a VR sport-oriented system can induce increased anxiety (physiological and subjective measures) compared to a baseline condition. There were a number of main effects and interaction effects for all three independent variables in terms of the subjective measures of anxiety. Both known anxiety triggers and simulation fidelity had a direct relationship to anxiety, while field of regard had an inverse relationship. Overall, the results demonstrate great potential for VR sport psychology training systems; however, further research is needed to determine if training in a VR environment can lead to long-term reduction in sport-induced anxiety.