Interaction of aberrations, diffraction, and quantal fluctuations determine the impact of pupil size on visual quality

The pseudophakic eye lacks the ability to produce a refractive change in response to object proximity. Thus, individual anatomical features such as the pupil size play an important role in achieving functional vision levels. In this work, the range of pupil sizes at varying object distance was measured in pseudophakic participants. Furthermore, the impact of the measured values on eye optical quality was investigated using a computer simulation model. A binocular eye-tracker was used to measure the participants’ pupil sizes at six object distances, ranging from 0.33 m (i.e., vergence of 3.00 D) to 3.00 m (i.e., vergence of 0.33 D), while observing a Maltese cross with a constant angular size of 1 ∘ . In total, 58 pseudophakic participants were enrolled in this study (age mean ± standard deviation: 70.5 ± 11.3 years). The effects of object distance and age on pupil size variation were investigated using linear mixed effects regression models. Age was found to have a small contribution to individual variability. The mean infinite distance pupil size (intercept) was 4.45 ( 95 % CI: 2.74, 6.17) mm and the mean proximal miosis (slope) was − 0.23 ( 95 % CI: −0.53, 0.08) mm/D. The visual acuity (VA) estimation for a distant object ranged from − 0.1 logMAR (smallest pupil) to 0.04 logMAR (largest pupil) and the near VA ( 0.33 m) when mean proximal miosis was considered ranged from 0.28 logMAR (smallest pupil) to 0.42 logMAR (largest pupil). When mean distance pupil was considered, proximal miosis individual variability produced a variation of 0.04 logMAR for the near object and negligible variation for the distant object. These results support the importance of distance pupil size measurement for the prediction of visual performance in pseudophakia, while suggesting that proximal miosis has a negligible impact in VA variability.

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ABSCISIC ACID DRENCHES IMPROVE POSTPRODUCTION SHELF LIFE OF IMPATIENS

HortScience ◽

10.21273/hortsci.41.3.511e ◽

2006 ◽

Vol 41 (3) ◽

pp. 511E-512

Author(s):

James L. Gibson ◽

Shannon Crowley

Keyword(s):

Abscisic Acid ◽

Visual Quality ◽

Light Environment ◽

Light Conditions ◽

Labor Costs ◽

Flower Number ◽

Low Light ◽

Quality Ratings ◽

Select Group ◽

The Impact

Foliar sprays or root dips of synthetic abscisic acid (s-ABA) have shown to reduce the transpiration rate and subsequently prolong postharvest longevity in a select group of herbaceous ornamental crops. The objective of our study was to determine the impact of s-ABA on postproduction performance of seed impatiens in greenhouse or low light conditions. Market ready Impatiens wallerana `Xtreme Scarlet' plants were sprayed or the root substrate was drenched with s-ABA at 250 or 500 mg·L–1 then boxed for 48 h to represent shipping conditions. Flower number was measured 3 days after application, and again after plants were hydrated following the day when the last treatment wilted 0, 2, 4, 8, 16, or 24 days after application. Visual quality ratings were made 0, 2, 3, 4, 8, 11, 16, or 19 days after application and again after plants were re-irrigated. Drenching the substrate with s-ABA at 500 mg·L–1 maintained foliage and flower turgidity up to 8 days in the greenhouse environment and 16 days in the low light environment. Substrate drenches at 500 mg·L–1 dramatically decreased flower number after removal from the shipping box under greenhouse conditions, and in the low light environment drenching the substrate at 250 mg·L–1 produced similar visual quality results to 500 mg·L–1 16 days after treatment. Plants drenched at 250 mg·L–1 also had the same number of flowers 3 and 20 days after treatment, when compared to 500 mg·L–1. Therefore, impatiens growers should drench the root substrate with s-ABA at 250 mg·L–1 to reduce labor costs associated with hand-watering and prolong postproduction performance in low light conditions, such as indoor retail conditions.

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Transcutaneous auricular vagus nerve stimulation increases eye-gaze on salient facial features and oxytocin release

10.1101/2021.09.12.459983 ◽

2021 ◽

Author(s):

Siyu Zhu ◽

Yanan Qing ◽

Yingying Zhang ◽

Xiaolu Zhang ◽

Fangyuan Ding ◽

...

Keyword(s):

Social Cognition ◽

Vagus Nerve ◽

Nerve Stimulation ◽

Vagus Nerve Stimulation ◽

Pupil Size ◽

Therapeutic Potential ◽

Fixation Time ◽

Facial Features ◽

Oxytocin Release ◽

The Impact

Background: Transcutaneous auricular vagus nerve stimulation (taVNS) is a non-invasive neuromodulation technique with promising therapeutic potential in the context of epilepsy, pain, and depression and which may also have beneficial effects on social cognition. However, the underlying mechanisms of taVNS are unclear and evidence regarding its role in social cognition improvement is limited. Objective: In order to investigate the impact of taVNS on social cognition we have studied its effects on gaze towards emotional faces using an eye-tracking task and also on release of the neuropeptide oxytocin which plays a key role in influencing social cognition and motivation. Methods: A total of fifty-four subjects were enrolled in a sham-controlled, participant-blind crossover experiment, consisting of two treatment sessions, separated by one week. In one session participants received 30-min taVNS (tragus), and in the other, they received 30-min sham (earlobe) stimulation with the treatment order counterbalanced across participants. Gaze duration towards the faces and facial features (eyes, nose, and mouth) were measured together with resting pupil size. Additionally, saliva samples were taken for the measurement of oxytocin concentrations by enzyme-linked immunoassay. Results: Saliva oxytocin concentrations increased significantly after taVNS compared to sham stimulation, while resting pupil size did not. In addition, taVNS increased fixation time on the nose region irrespective of face emotion, and this was positively correlated with increased saliva oxytocin concentrations. Conclusion: Our findings suggest that taVNS biases visual attention towards socially salient facial features across different emotions and this is associated with its effects on increasing endogenous oxytocin release.

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Comparative analysis of the clinical outcomes between wavefront-guided and conventional femtosecond LASIK in myopia and myopia astigmatism

International Journal of Ophthalmology ◽

10.18240/ijo.2021.10.16 ◽

2021 ◽

Vol 14 (10) ◽

pp. 1581-1588

Author(s):

Xiao Gui ◽

◽

Sha Li ◽

Na Zhao ◽

Hao-Rui Zhang ◽

...

Keyword(s):

Clinical Outcomes ◽

Pupil Size ◽

High Myopia ◽

Visual Quality ◽

Comparative Investigation ◽

Uncorrected Distance Visual Acuity ◽

Efficacy Index ◽

Better Than ◽

High Order Aberrations

AIM: To compare the clinical outcomes of wavefront guided femtosecond LASIK (WFG LASIK) and conventional femtosecond LASIK (NWFG LASIK) in eyes with myopia and myopia astigmatism. METHODS: This was a retrospective, nonrandomized, comparative investigation enrolling 236 eyes of 122 patients (18-50y) with low & moderate and high myopia. The WFG group including 97 eyes (50 patients) undergone WFG LASIK and the NWFG group including 139 eyes (72 patients) undergone conventional LASIK. Mean efficacy index, high order aberrations (HOAs), pupil size and the quality of visual questionnaire were evaluated 6mo postoperatively. RESULTS: There is no difference between WFG group (-0.054±0.049 in logMAR) and NWFG group (-0.040±0.056) in uncorrected distance visual acuity (UDVA) postoperatively. The myopia astigmatism is higher in WFG group than that in NWFG group (P<0.05). However, the mean efficacy index (MEI) in the WFG group (1.09±0.106) is better than that in the NWFG group (1.036±0.124; P<0.001). Increased HOAs were observed in NWFG group (0.30±0.196) than that in WFG group (0.146±0.188; P<0.001). The pupil size is larger in WFG group (5.15±0.76 mm) than that in NWFG group (4.32±0.52 mm). The patients are satisfied with the clinical surgery, yet WFG group showed better visual quality using the questionnaire survey. Meanwhile, high myopia would result in worse MEI, HOAs and visual quality than low & moderate myopia. CONCLUSION: WFG and NWFG FS-LASIK are both effective and safe procedures to correct low & moderate and high myopia, but WFG FS-LASIK gives a better postoperative MEI, aberrometric control and predictable outcome. Meanwhile, WFG FS-LASIK is better than NWFG FS-LASIK in correction of myopia astigmatism. Low & moderate myopia allow better clinical outcomes than high myopia using any surgical method.

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‘On the very Verge of legitimate Invention’: Charles Bonnet and William Blake’s illustrations to Robert Blair’s The Grave (1808)

The Gothic and Death ◽

10.7228/manchester/9781784992699.003.0003 ◽

2017 ◽

Author(s):

Sibylle Erle

Keyword(s):

Death And Dying ◽

Visual Quality ◽

European Context ◽

The Impact ◽

Immortality Of The Soul

This chapter discusses William Blake’s response to Johann Caspar Lavater’s Essays on Physiognomy (178998) and awareness of Charles Bonnet’s ideas about the afterlife in order to highlight the complexity of Blake’s illustrations to the new edition of Robert Blair’s The Grave published by R. H. Cromek in 1808. Blake was extremely fond of drawing souls. It is, however, often impossible to tell a rendering of living soul from a dead one. This chapter examines Blake’s relationship with the Gothic’s preoccupation with death and dying and explains, via the European context, how the impact of Blake’s images supersedes the Gothic and visual quality of language of Blair’s text. Blake’s drawings of the spiritual are not spontaneous sketches but evidence for his awareness of Lavater’s physiognomical theory and specifically the European debate about the immortality of the soul.

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THE RESEARCH ON THE IMPACT ASSESSMENT OF VISUAL LANDSCAPE OF COUNTRY PARKS IN BEIJING

Journal of Environmental Engineering and Landscape Management ◽

10.3846/16486897.2015.1106545 ◽

2016 ◽

Vol 24 (1) ◽

pp. 37-47 ◽

Cited By ~ 1

Author(s):

Chuanan LIU ◽

Tong QI ◽

Xiao MA

Keyword(s):

Impact Assessment ◽

Visual Space ◽

Visual Quality ◽

First Grade ◽

Visual Disturbance ◽

Absorption Capacity ◽

Visual Environment ◽

Entropy Weight ◽

The Impact

The attribute of a country park and its visual environment are not only influenced by the distance from the park to the downtown area, but also the degree of urbanization. Based on the landscape geography, landscape ecology, landscape aesthetics theories and the Guideline for Technical Review of Environmental Impact Assessment of Construction Projects (HJ 616-2011) and aiming to evaluate the visual quality of the country parks, we put forward three first-grade indicators (visual sensitive capacity, visual space capacity and visual absorption capacity) and seven second grade indicators (sighting distance, visual disturbance frequency, green looking ratio, inter-visibility, openness, relative angle and the relative area of artificial matrix) in our research. By virtue of the established entropy weight method model, combined with field data, the quantitative research of the visual environment of landscape in country parks was carried out so that the visual quality of the park can be improved. At same time, this can also provide a scientific basis for spatial planning of urban fringe area and repositioning of the park attribute.

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Effect of Single Administration of Coffee on Pupil Size and Ocular Wavefront Aberration Measurements in Healthy Subjects

BioMed Research International ◽

10.1155/2016/9578308 ◽

2016 ◽

Vol 2016 ◽

pp. 1-5 ◽

Cited By ~ 10

Author(s):

Handan Bardak ◽

Murat Gunay ◽

Ugur Mumcu ◽

Yavuz Bardak

Keyword(s):

Pupil Size ◽

Healthy Subjects ◽

Spherical Aberration ◽

Ultrastructural Changes ◽

Wavefront Aberration ◽

Single Administration ◽

Coffee Intake ◽

Coffee Drinking ◽

Acute Changes ◽

The Impact

No study has so far evaluated the impact of coffee drinking on ocular wavefront aberration (OWA) measurements. This study presents novel findings regarding the OWA of the eye following coffee intake. We aimed to evaluate the acute changes in pupil size and OWA of the eye after single administration of coffee. A total of 30 otherwise healthy participants were included in this prospective study. All subjects drank a cup of coffee containing 57 mg caffeine. Measurements of pupil size, total coma (TC), total trefoil (TF), total spherical aberration (TSA), and total higher order aberration (HOA) were performed before and at 5 minutes, at 30 minutes, and at 4 hours after coffee drinking using a wavefront aberrometer device (Irx3, Imagine Eyes, Orsay, France). The mean age of the study population was 20.30 ± 2.74 years. Pupil size did not show a significant change during the measurements (p>0.05). A significant increase was observed in TF and HOA measurements following coffee intake (p=0.029andp=0.009, resp.). Single administration of coffee results in significant increase in TF and total HOAs in healthy subjects without any effect on pupil diameter. Ultrastructural changes in the cornea following coffee intake might be of relevance to the alterations in ocular aberrations in healthy subjects.

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Expendable or valuable?

Journalistica - Tidsskrift for forskning i journalistik ◽

10.7146/journalistica.v15i1.125417 ◽

2021 ◽

Vol 15 (1) ◽

Author(s):

Maria Nilsson

Keyword(s):

Structural Changes ◽

Qualitative Interviews ◽

Visual Quality ◽

External Factors ◽

Organizational Changes ◽

Breaking News ◽

Competitive Edge ◽

External Sources ◽

Visual Strategies ◽

The Impact

This study explores the impact of organizational changes on newspaper photo departments, an area of newsrooms that have arguably been particularly affected by structural changes in the field of journalism Through qualitative interviews with editors responsible for photojournalism at five Swedish newspapers that have experienced recent changes to photo staffing and routines for the sourcing of images, the study explores the following questions: Which routines do the newspapers have for sourcing images, in terms of in-house staff and external sources? How do notions of visual quality and external factors, such as audiences and competition, contribute to shaping the newspapers’ visual strategies? Findings indicate that newspapers rely on staff photojournalists for unique and in-depth coverage, but less for routine and breaking news. A certain expansion of photojournalism was found in some newsrooms where it is seen as a competitive edge; which, in part, challenges a “discourse of doom.” Uncertainty about the support for visual strategies in newsrooms lacking visual leadership was also found.

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КОМБІНОВАНА МЕТРИКА ВІЗУАЛЬНОЇ ЯКОСТІ ЗОБРАЖЕНЬ ДИСТАНЦІЙНОГО ЗОНДУВАННЯ НА ОСНОВІ НЕЙРОННОЇ МЕРЕЖІ

RADIOELECTRONIC AND COMPUTER SYSTEMS ◽

10.32620/reks.2020.4.01 ◽

2020 ◽

pp. 4-15

Author(s):

Олег Игоревич Еремеев ◽

Владимир Васильевич Лукин ◽

Krzysztof Okarma

Keyword(s):

Neural Network ◽

Quality Assessment ◽

Rank Order ◽

Selection Criterion ◽

Visual Quality ◽

Quality Metrics ◽

Visual Quality Assessment ◽

Joint Application ◽

Subjective Estimates ◽

The Impact

The wide distribution of images of remote sensing (RS) of the Earth in various application areas makes it important to ensure the high quality of such images, which is important to identify necessary information. The complexity of the systems and the impact of various physical processes cause a significant number of distortions that lead to image corruption and possible loss of information. The use of processing methods that should reduce the impact of such factors requires control of their work, which uses quantitative indicators of visual quality. The article considers the task of creating a combined visual quality metric based on an artificial neural network (ANN), which provides high accuracy of visual quality assessment and stability of work on the noise characteristic of the RS. The problem of analysis of RS distortions is considered and the approach of using the database of test images TID2013 for verification on typical RS distortions is offered. The analysis of well-known visual quality metrics and their suitability for the estimation of such images is carried out. According to its results, it was determined that the best metrics provide the accuracy of image quality assessment for RS tasks at the level of 0.93 according to Spearman's rank-order correlation coefficient with subjective estimates of the TID2013 image database. The joint application of existing quality metrics allows eliminating the shortcomings of each of them and increasing the overall efficiency, so the article considers the problems and defines the requirements for creating a combined metric involving a neural network. A method of limiting the number of involved quality metrics with the involvement of Lasso regularization is proposed, which allows determining the most informative features (quality metrics) and simplifying the procedure of selection and reduction of their number. A study was conducted on the influence of the metric selection criterion and quantity on the accuracy of the combined metric. The influence of the structure of the neural network, the number of hidden layers, and the number of neurons in them are also analyzed. Based on the obtained results, the best implementation of ANN was selected, which with the involvement of 16 visual quality metrics allows achieving the accuracy of visual quality assessment at 0.97 according to Spearman's correlation with subjective estimates of the TID2013 database.

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