Visual Measurements Research Articles

The Role of Information Processing as an Underlying Mechanism in the Experience of Anxiety Reactivity and Anxiety Perseveration, Two Dissociable Dimensions of Trait Anxiety

Abstract Purpose While long considered a unitary dimension, research has moved towards a multidimensional understanding of trait anxiety, and has identified two dissociable dimensions of trait anxiety: anxiety reactivity and anxiety perseveration. Despite the consolidation of this understanding over the past decade, the mechanisms underlying these two dimensions are not well established. The present study examined the novel role of information processing in the experience of anxiety reactivity and perseveration, specifically, how enhanced processing of situational information influences reactivity, and how enhanced processing of implicational information influences perseveration. Method Undergraduate university students (N = 142) were exposed to an interview-based stressor. As participants approached this stressor, they were provided with information reflecting one of the two content categories, intended to encourage a situational or implicational processing mode. Anxiety reactivity and anxiety perseveration were measured by assessing changes in state anxiety (measured using a single item visual analogue state anxiety measure) in the lead up and wake of this stressor. Results Mixed-design ANOVAs did not reveal a significant relationship between enhanced processing of situational information and anxiety reactivity, nor between enhanced processing of implicational information and anxiety perseveration. An experimental manipulation involving valence revealed that receiving positive information reduced the intensity of state anxiety elevations in the aftermath of the information processing task. Conclusions Findings are discussed with reference to limitations and future extensions that could investigate the potential role of cognitive biases in this proposed relationship between enhanced information processing and anxiety reactivity and perseveration.

A Novel Real-Time Autonomous Localization Algorithm Based on Weighted Loosely Coupled Visual–Inertial Data of the Velocity Layer

IMUs (inertial measurement units) and cameras are widely utilized and combined to autonomously measure the motion states of mobile robots. This paper presents a loosely coupled algorithm for autonomous localization, the ICEKF (IMU-aided camera extended Kalman filter), for the weighted data fusion of the IMU and visual measurement. The algorithm fuses motion information on the velocity layer, thereby mitigating the excessive accumulation of IMU errors caused by direct subtraction on the positional layer after quadratic integration. Furthermore, by incorporating a weighting mechanism, the algorithm allows for a flexible adjustment of the emphasis placed on IMU data versus visual information, which augments the robustness and adaptability of autonomous motion estimation for robots. The simulation and dataset experiments demonstrate that the ICEKF can provide reliable estimates for robot motion trajectories.

Groundwater flow velocity and direction measurement sensor based on an equivalent pendulum model and visual measurement

Groundwater flow velocity and direction measurement sensor based on an equivalent pendulum model and visual measurement

Validity and reliability of the Swedish version of the Visual CARE Measure for assessing children’s perceptions of nurses’ empathy

The purpose of this study was to translate and validate a questionnaire to be used by children with chronic diseases during procedures. Specific research questions were as follows: Is the translated versions reliable? Is there a correlation between VCM and another questionnaire measuring discomfort to enhance the validity of VCM? The three versions of Visual CARE measure (VCM) were translated following the principles of good practice for translation and cultural adaptation of patient-reported outcome measures, according to the International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Cognitive debriefing interviews with children, parents, and healthcare professionals were carried out. The correlation between empathy and discomfort was evaluated using DISCO-RC. The final versions of VCM were administered to children and their parents after a needle procedure or a nasal tube insertion. The Cronbach’s alpha was 0.89 for the 5Q version, 0.93 for the 10Q version, and 0.96 for the 10Q-Parent version, which implies high internal consistency. The intra-class correlation was 0.623 for VCM 5Q, with a mean difference of 1.35 and an ICC of 0.767 for VCM 10Q, with a mean difference of 1.17. This is considered a good agreement between children’s and their parents’ assessments. A significant difference in the children’s reports could be seen when experiencing high discomfort as opposed to low discomfort.Conclusion: VCM is a useful Patient-Reported Experience Measure (PREM) that can help enhance the quality of care for children in a paediatric setting by capturing their perception of the empathy shown.What is known:• Parents’ by-proxy reports are not always aligned with children’s self-reports. In healthcare situations, children can be hurt when they are ignored.• Research shows that empathic encounters relieve distress, improve the relationship between the patient (who could be a child) and carer, and create an open, trusting relationship.What is new:• This study shows that all three versions of the Visual CARE Measure are valid for assessing children’s experience of empathy shown by nurses during a procedure..• This is one of the first studies that confirms the correlation between children’s experience of nurses’ levels of empathy and the child’s discomfort.• This study shows that the Visual CARE Measure can support the evaluation of children’s rights with regards to communication in a clinical context.

Topographic factors associated with anterior chamber angle narrowing in patients with keratoconus.

To identify topographic determinants of the anterior chamber angle (ACA) in patients with keratoconus (KCN). Four hundred and ten eyes of 294 patients with KCN were recruited for this study. First, complete ocular examinations were performed for all patients, including visual acuity measurement, refraction, and slit-lamp biomicroscopy. Then, all participants underwent corneal imaging by the Oculus Pentacam HR. The mean age of the participants was 32.40±8.52y (15-60y) and 69.5% of them were male. The mean ACA was 38.47°±5.75° (range: 14.40° to 56.50°) in the whole sample, 38.24°±6.00° in males, and 38.98°±5.11° in females (P=0.447). The mean ACA was significantly different among different groups of cone morphology, as patients with nipple cones showed the lowest mean ACA. Moreover, there were statistically significant differences in the mean ACA among different groups of cone locations, with patients having central cones exhibiting the lowest mean ACA (P<0.001). Anterior and posterior Q values were significantly, directly correlated with ACA (anterior Q: r=0.122, P=0.014, posterior Q: r=0.192, P<0.001). This study provides critical insights into the risk factors for ACA narrowing in KCN patients, which is essential for planning intraocular surgeries. Patients with nipple and central cones exhibited the most significant ACA narrowing. Additionally, more negative Q-values are associated with increased ACA narrowing, highlighting the need for targeted diagnostic and therapeutic strategies.

Uncertainties in Ground‐Based Visual Double Star Measures

Uncertainties in Ground‐Based Visual Double Star Measures

Advancements in molecular imaging probes for precision diagnosis and treatment of prostate cancer.

Prostate cancer is the second most common cancer in men, accounting for 14.1% of new cancer cases in 2020. The aggressiveness of prostate cancer is highly variable, depending on its grade and stage at the time of diagnosis. Despite recent advances in prostate cancer treatment, some patients still experience recurrence or even progression after undergoing radical treatment. Accurate initial staging and monitoring for recurrence determine patient management, which in turn affect patient prognosis and survival. Classical imaging has limitations in the diagnosis and treatment of prostate cancer, but the use of novel molecular probes has improved the detection rate, specificity, and accuracy of prostate cancer detection. Molecular probe-based imaging modalities allow the visualization and quantitative measurement of biological processes at the molecular and cellular levels in living systems. An increased understanding of tumor biology of prostate cancer and the discovery of new tumor biomarkers have allowed the exploration of additional molecular probe targets. The development of novel ligands and advances in nano-based delivery technologies have accelerated the research and development of molecular probes. Here, we summarize the use of molecular probes in positron emission tomography (PET), single-photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), optical imaging, and ultrasound imaging, and provide a brief overview of important target molecules in prostate cancer.

Influence of Visual Quality and Cultural Background on Consumer Apple Preferences: An Eye-Tracking Study with Chinese and Hungarian Consumers

Using eye-tracking technology, the proposed study investigates how customers visually evaluate apples varieties and apple defects and how these evaluations affect their purchasing decisions. Three aspects were examined in this study: apple variety, defect severity, and cultural background. Idared, Golden Delicious Yellow, and Golden Delicious Green apple varieties with increasing degrees of bruising were shown to Chinese and Hungarian participants. The findings show that apple variety had no significant effect on gaze patterns, whereas cultural background had a considerable impact on visual attention measures. The most important element in grabbing and retaining customer attention was the severity of the defect, which was measured by area. The “Threshold of Rejection”, which characterizes consumer tolerance for Apple defects, is introduced in the study. Furthermore, a polynomial regression model was created to predict the probability of repurchasing an apple depending on its visual quality (level of bruising). These results provide useful information for marketing plans, quality assurance, and comprehending customer behavior in the fresh produce sector.

Relationship Between Intraocular Pressure and the True Rate of Functional and Structural Progression in the United Kingdom Glaucoma Treatment Study.

To investigate the effect of average intraocular pressure (IOP) on the true rate of glaucoma progression (RoP) in the United Kingdom Glaucoma Treatment Study (UKGTS). UKGTS participants were randomized to placebo or Latanoprost drops and monitored for up to two years with visual field tests (VF, 24-2 SITA standard), IOP measurements, and optic nerve imaging. We included eyes with at least three structural or functional assessments (VF with <15% false-positive errors). Structural tests measured rim area (RA) with Heidelberg retina tomography (HRT) and average peripapillary retinal nerve fiber layer (pRNFL) thickness with optical coherence tomography (OCT). One eye of 436 patients (222 on Latanoprost) was analyzed. A Bayesian hierarchical model estimated the true RoP of VF and structural metrics, and their correlations, using sign-reversed multivariable exponential distribution. RA and pRNFL measurements were converted to a dB scale, matching the VF metric (mean deviation [MD]). The effect of average IOP on the true RoPs was estimated. True RoP at the mean average IOP (17 mm Hg) was faster (P < 0.001) for VF-MD (-0.59 [-0.73, -0.48] dB/year) than HRT-RA (-0.05 [-0.07, -0.03] dB/year) and OCT-pRNFL (-0.08 [-0.11, -0.06] dB/year). The proportional acceleration of RoP per mm Hg increase was, however, not significantly different (smallest P = 0.15). Accounting for the structural floor-effect largely eliminated the differences in RoPs (smallest P = 0.25). VF appeared to deteriorate at a faster rate than structural measurements. However, this could be explained by the floor-effect from nonfunctional tissue. IOP induced a similar acceleration in RoP per mm Hg increase.

A laser tracking attitude dynamic measurement method based on real-time calibration and AEKF with a multi-factor influence analysis model

Abstract To address the limitations of six-degree-of-freedom (6-DOF) visual tracking systems in terms of low dynamic performance and the inability to perform measurements under light occlusion, this paper proposes a novel laser tracking attitude dynamic measurement method integrating vision and inertial measurement unit (IMU). A tailored real-time calibration model is developed to enable precise alignment of the vision and IMU coordinate systems during dynamic operations. To overcome the limitations of extended Kalman filter (EKF) that rely on static noise assumptions in complex dynamic measurement scenarios, this study proposes an adaptive mechanism based on multi-factor influence analysis. Through dynamic monitoring of visual observation noise, an adaptive EKF algorithm is designed to enhance performance under varying conditions. When integrated into a vision/IMU fusion system, the algorithm significantly enhances the system’s sensitivity to variations in visual sensor observation noise caused by changes in lighting and motion states. This capability allows rapid adjustment of filtering parameters, leading to substantial improvements in filtering accuracy and stability. Simulation results demonstrate that the proposed algorithm outperforms traditional EKF in fusion measurement accuracy when tested in simulated noise environments featuring sinusoidal and random jump signals. Furthermore, the fusion measurement accuracy is mainly influenced by the data density of the visual sensor and the measurement distance. Finally, the proposed method was validated on a precision turntable. Experimental results reveal that at a 3 m measurement distance and within a 0°–25° angular range, when the turntable rotates at a constant speed of 5°/s along a single axis, the maximum absolute deviation in repeatability of the fused attitude measurements was below 0.11°, and the system is capable of achieving a high measurement frequency of 100 Hz.

Clinical Importance of Protein Intake in Hospitalized Elderly Patients With Heart Failure.

The relationship between protein intake and the long-term prognosis of elderly patients with heart failure remains poorly understood. We investigated the association between predischarge protein intake and long-term prognosis in hospitalized elderly patients with heart failure. A single-center, retrospective analysis of hospitalized patients aged ≥65 years with heart failure and reduced ejection fraction was conducted. Protein intake was evaluated by nutritionists based on visual measurements of the percentage of dietary intake obtained for 7 days before discharge by a nurse. A cutoff of 1.2 g/kg/day protein intake was used to compare the incidence of a composite endpoint, including all-cause mortality and heart failure rehospitalization within 1 year. Among the 100 patients (median age 79 years; 47% male), 56% had low protein intake (<1.2 g/kg/day). Patients with low protein intake had a significantly higher rate of composite endpoints than those with high protein intake (50% vs. 20%; log-rank test P=0.03). Multivariable Cox proportional hazards model revealed that low protein intake was independently associated with long-term prognosis with a hazard ratio of 2.73 and a 95% confidence interval of 1.10-6.80 (P=0.03). Low protein intake in the predischarge phase was associated with long-term prognosis in hospitalized elderly patients with heart failure and reduced ejection fraction.

Based on the Geometric Characteristics of Binocular Imaging for Yarn Remaining Detection.

The automated detection of yarn margins is crucial for ensuring the continuity and quality of production in textile workshops. Traditional methods rely on workers visually inspecting the yarn margin to determine the timing of replacement; these methods fail to provide real-time data and cannot meet the precise scheduling requirements of modern production. The complex environmental conditions in textile workshops, combined with the cylindrical shape and repetitive textural features of yarn bobbins, limit the application of traditional visual solutions. Therefore, we propose a visual measurement method based on the geometric characteristics of binocular imaging: First, all contours in the image are extracted, and the distance sequence between the contours and the centroid is extracted. This sequence is then matched with a predefined template to identify the contour information of the yarn bobbin. Additionally, four equations for the tangent line from the camera optical center to the edge points of the yarn bobbin contour are established, and the angle bisectors of each pair of tangents are found. By solving the system of equations for these two angle bisectors, their intersection point is determined, giving the radius of the yarn bobbin. This method overcomes the limitations of monocular vision systems, which lack depth information and suffer from size measurement errors due to the insufficient repeat positioning accuracy when patrolling back and forth. Next, to address the self-occlusion issues and matching difficulties during binocular system measurements caused by the yarn bobbin surface's repetitive texture, an imaging model is established based on the yarn bobbin's cylindrical characteristics. This avoids pixel-by-pixel matching in binocular vision and enables the accurate measurement of the remaining yarn margin. The experimental data show that the measurement method exhibits high precision within the recommended working distance range, with an average error of only 0.68 mm.

Unusual Temperature-Dependent Photoluminescence Due to Competing Excited-State Energy Transfer in Rare Earth Double Perovskites.

Lead-free halide double perovskites (DPs) have become a research hotspot in the field of photoelectrons due to their unique optical properties and flexible compositional tuning. However, the luminescence of DPs exhibits thermal quenching at high temperatures, which severely affects their further application. Herein, we synthesized the rare earth Dy3+ and transition metal Mn2+ codoped Cs2NaYCl6 rare earth DPs and characterized the optical properties using temperature-dependent photoluminescence spectra and time-resolved photoluminescence decay profiles at different temperatures. The Mn2+-Dy3+:Cs2NaYCl6 DPs exhibit stronger luminescence with increasing temperature, attributed to antithermal quenching. The successful incorporation of Mn dopants in the DPs lattice results in suppression of nonradiative recombination, more efficient energy transfer (ET) to Dy3+, and a reduced lattice distortion. These kinds of DPs with near-infrared luminescence have promising prospects in applications such as night vision, radiation detection, solid-state lighting, and optical temperature measurement.

HIGH-RESOLUTION VISUALIZATION MEASUREMENT OF VORTEX-SHEDDING AT HIGH FREQUENCIES USING SUB-NYQUIST-RATE PIV AND COMPRESSED SENSING

Oscillating flows appear in various applications, such as vortex shedding in vehicles, wings, and structures, as well as pulsating flows in pipes. While time-resolved particle image velocimetry (PIV) is often employed for these measurements, high-speed cameras are required to capture high-frequency oscillations, which increases cost and reduces spatial resolution. This study employs a low-speed, high-resolution camera to achieve high-spatial-resolution visualization measurements. Compressed sensing was utilized to compensate for the lack of time resolution, thereby enabling the measurement of high-frequency velocity oscillations. Random sampling, essential for compressed sensing, was performed by randomizing the exposure times of two time-delayed cameras. Proper orthogonal decomposition was used to identify spatial modes, and correction of nonstationary amplitude modulation was performed using attractors of the time functions of the two paired modes. The proposed method successfully reconstructed the flow with a Reynolds number of 250 and a vortex shedding frequency of 73.5 Hz from 20 velocity field data points obtained at 30 Hz. The reconstruction error for the entire velocity field was 11&amp;#37;, effectively reproducing vortex shedding, advection, and diffusion behaviors. The newly developed correction method for amplitude modulation can be applied to other visualization and measurement techniques using compressed sensing.

Study on Visual Quality After Cataract Surgery and Goniosynechialysis in Patients with Primary Angle-Closure Glaucoma and Cataracts.

To assess the visual quality in patients with primary angle-closure glaucoma (PACG) complicated by cataracts after cataract phacoemulsification with intraocular lens (IOL) implantation and goniosynechialysis, and to explore the relationship between pupil size and visual quality. A retrospective, non-randomized study was conducted, including 65 PACG patients (75 eyes) who underwent cataract surgery with IOL implantation and goniosynechialysis from July 2021 to June 2023, as well as a control group of cataract-only patients. Visual quality was evaluated using objective and subjective methods at least 3 months postoperatively. PACG patients were divided into large-pupil (≥5 mm) and normal-pupil (<5 mm) groups. Visual quality parameters were compared among groups, and correlations between pupil size and objective visual quality measures were analyzed. Visual Parameters: The large-pupil PACG group showed significantly higher higher-order aberrations, including coma and spherical aberrations, compared to both the cataract and normal-pupil groups. Contrast sensitivity was also worse in the large-pupil group. Visual Quality Questionnaire: The large-pupil group reported higher scores for night glare and difficulty driving at night. Correlations: Pupil size was positively correlated with higher-order aberrations and negatively correlated with contrast sensitivity. Pupil dilation is a major factor affecting postoperative visual quality in PACG patients, even after surgery. Larger pupil size significantly increases higher-order aberrations and reduces contrast sensitivity. Techniques like pupil suturing may help improve visual quality in these patients.

The retinal structure and visual function in asymptomatic individuals carrying leber hereditary optic neuropathy mutation

Purpose: To evaluate the retinal structure and visual function in asymptomatic subjects with Leber hereditary optic neuropathy (LHON) mutation. We evaluated macular ganglion cell layer and inner plexiform layer (GCL+IPL) and peripapillary retinal nerve fiber layer (RNFL) and assessed high and low contrast visual acuity and visual field sensitivity.Methods: A total of 28 asymptomatic carriers (37±20 years), 53.5% females, were enrolled. 100% and 13% contrast visual acuity, visual field sensitivity, and Optic coherence tomography (OCT) were performed. Visual field was evaluated with Humphrey Field Analyzer 3 using SITA 24‐2 strategy with white‐on‐white size III stimuli. OCT imaging was performed with a Zeiss Cirrus 5000 HD‐OCT using macular cube 512x128 scan, and optic disc cube 200x200 scan. The thickness and visual function metrics obtained were analyzed to investigate within‐subject differences. For each subject, the eyes were divided into best and worst based on the visual function parameters and as thickest and thinnest based on the structural measurements.Results: The mean difference between best and worst eye for 100% and 13% visual acuity were 0.03 ± 0.05 (range: 0 to 0.23) and 0.05 ± 0.06 logMAR (range: 0 to 0.18) respectively. For the mean deviation from visual field measurements varied by 1.11 ± 0.85 dB (range: 0.10 to 3.19) between the eyes. The mean difference between thickest and thinnest eye for GCL+IPL and RNFL were 1.48 ± 1.45 μm (range: 0 to 6) and 3.22 ± 2.85 μm (range: 0 to 9) respectively. All the visual function metrics and the structural measurements displayed small but statistically significant inter‐eye differences (p &lt; .005).Conclusions: In asymptomatic LHON carriers inter‐eye differences were found in structural and functional measurements. OCT imaging and precise visual function test may provide useful information about disease conversion risk in asymptomatic carriers.

Hovering hawkmoths exploit unsteady circulation to produce aerodynamic force.

This study employs an integrated approach, combining three-dimensional flow visualization and two-dimensional flow measurement to investigate the underlying unsteady aerodynamic mechanisms of hovering hawkmoths. Using a single vortex ring model, three aerodynamic force components, such as aerodynamic force induced by unsteady circulation, vortex loop size variation and added mass, are estimated within a dimensionless time (normalized by one wing beat cycle) range of 0.418 < T* < 0.455, where both the vortex loop circulation and loop size data are available. The force analysis reveals that the unsteady circulation-induced aerodynamic force dominates the overall force production and contributes 67% of the total force while the vortex loop size variation and added mass effect-induced aerodynamic forces only count for 25% and 8%, respectively. These findings suggest the hawkmoth primarily relies on unsteady circulation to generate aerodynamic forces.

The retinal structure and visual function in asymptomatic individuals carrying leber hereditary optic neuropathy mutation

Purpose: To evaluate the retinal structure and visual function in asymptomatic subjects with Leber hereditary optic neuropathy (LHON) mutation. We evaluated macular ganglion cell layer and inner plexiform layer (GCL+IPL) and peripapillary retinal nerve fiber layer (RNFL) and assessed high and low contrast visual acuity and visual field sensitivity.Methods: A total of 28 asymptomatic carriers (37±20 years), 53.5% females, were enrolled. 100% and 13% contrast visual acuity, visual field sensitivity, and Optic coherence tomography (OCT) were performed. Visual field was evaluated with Humphrey Field Analyzer 3 using SITA 24‐2 strategy with white‐on‐white size III stimuli. OCT imaging was performed with a Zeiss Cirrus 5000 HD‐OCT using macular cube 512x128 scan, and optic disc cube 200x200 scan. The thickness and visual function metrics obtained were analyzed to investigate within‐subject differences. For each subject, the eyes were divided into best and worst based on the visual function parameters and as thickest and thinnest based on the structural measurements.Results: The mean difference between best and worst eye for 100% and 13% visual acuity were 0.03 ± 0.05 (range: 0 to 0.23) and 0.05 ± 0.06 logMAR (range: 0 to 0.18) respectively. For the mean deviation from visual field measurements varied by 1.11 ± 0.85 dB (range: 0.10 to 3.19) between the eyes. The mean difference between thickest and thinnest eye for GCL+IPL and RNFL were 1.48 ± 1.45 μm (range: 0 to 6) and 3.22 ± 2.85 μm (range: 0 to 9) respectively. All the visual function metrics and the structural measurements displayed small but statistically significant inter‐eye differences (p &lt; .005).Conclusions: In asymptomatic LHON carriers inter‐eye differences were found in structural and functional measurements. OCT imaging and precise visual function test may provide useful information about disease conversion risk in asymptomatic carriers.

Structure design of industrial robot feeding and detecting workstation based on vision measurement principle

Structure design of industrial robot feeding and detecting workstation based on vision measurement principle

Structural design of a small module spur cylindrical gear measuring instrument based on machine vision measurement

Structural design of a small module spur cylindrical gear measuring instrument based on machine vision measurement