scholarly journals The Effect of Optical Defocus on the Choroidal Thickness: A Review

2021 ◽  
Vol 15 (1) ◽  
pp. 283-287
Author(s):  
Sulaiman Aldakhil

The choroid is a heavily vascularized tissue located between the retina and sclera and plays a primary role in ocular metabolism. It has recently been suggested that the choroid has the ability to change its thickness and secretion of growth factors. This may play an important role during visual development by adjusting retinal position during growth to support emmetropisation; however, the mechanism by which changes in choroidal thickness (ChT) occur is unclear. This relationship becomes an interesting topic in the clinical field, although conflicting evidence found that these changes in the choroidal thickness may not be associated with the development of refractive errors. Many reports have investigated the changes in the choroid and related factors that affect the ChT. Thus, this review will summarize the current literature related to choroidal thickness in different refractive error groups, determine the factors that influence the thickness of the choroid, and discuss in detail the relationship between the changes in the ChT and ocular elongation, and therefore, the effect of optical defocus on ChT and the development of the refractive error.

2020 ◽  
Vol 1 (4) ◽  
pp. 256-261
Author(s):  
Ying Zhou ◽  
◽  
Er-Teng Jia ◽  

This article summarized the choroidal thickness systematically and followed by relevant findings which describes the influencing factors of the choroidal thickness, the changes of the choroidal thickness in ophthalmic diseases and the relationship between the blood flow and the choroidal thickness detailedly. Choroidal thickness is affected by many factors, such as age, gender, intraocular pressure, refractive error, axial length, systolic blood pressure, daily rhythm, body position, smoking history, etc., and choroid is significantly correlated with many ophthalmic diseases. Choroidal thickness is of great importance in the diagnosis and treatment of ophthalmic diseases.


2021 ◽  
pp. 1-7
Author(s):  
Salam Chettian Kandi ◽  
Hayat Ahmad Khan

<b><i>Introduction:</i></b> Uncorrected refractive errors and amblyopia pose a major problem affecting schoolchildren. We had previously observed that many schoolchildren in the Hatta region presented to the ophthalmology clinic with uncorrected refractive errors and amblyopia, which led us to undertake this research. As per the WHO, the term “visual impairment” can be “low vision” or “blindness.” Based on the presenting vision, “low vision” is defined for children who have vision of &#x3c;6/18 to 3/60 or having visual field loss to &#x3c;20° in the better-seeing eye. Children defined to have “blindness” have presenting vision of &#x3c;3/60 or corresponding visual field of &#x3c;10°. <b><i>Purpose:</i></b> To estimate the magnitude of uncorrected refractive errors and amblyopia among the schoolchildren aged 6–19 years and to assess the efficacy of school-based refractive error screening programs in the Hatta region of the United Arab Emirates. <b><i>Methods:</i></b> An epidemiological, cross-sectional, descriptive study was conducted on the entire student population studying in the government schools of the region. Those who failed the Snellen visual acuity chart test and those who were wearing spectacles were evaluated comprehensively by the researcher in the Department of Ophthalmology of the Hatta Hospital. Data were entered in the Refractive Error Study in School Children (RESC) eye examination form recommended by the WHO, and were later transferred to Excel sheets and analyzed by SPSS. <b><i>Results:</i></b> 1,591 students were screened and evaluated from the end of 2016 to mid-2017. About 21.37% (<i>n</i> = 340) had impaired vision with 20.9% (<i>n</i> = 333) refractive errors, of which 58% were uncorrected. Among the refractive error group, 19% (64 subjects) had amblyopia (4% of total students). The incidence of low vision was 9.5% and blindness was 0.38%. Low vision was found to be 9.5% and blindness 0.38%, taking in to account presenting visual acuity rather than best-corrected visual acuity for defining low vision and blindness. <b><i>Conclusion:</i></b> A significant number of students were detected to have uncorrected refractive errors among the vision impaired group (59%, <i>n</i> = 197) despite a school-based vision screening program in place. Seventy-eight percent of the amblyopia cases (<i>n</i> = 50) were found to be in the 11–19 years age group. Noncompliance with optical corrections was the reason for the high number of cases. A rigorous vision screening program and refractive services, complimented with awareness among parents and teachers, are recommended.


2021 ◽  
pp. 234094442110022
Author(s):  
Lukas Timbate

There is a debate in academia and the business world on whether tax payments should be considered part of firms’ social responsibility. Existing literature provides conflicting evidence on the relationship between corporate tax payments and corporate social responsibility (CSR). Borrowing a concept from a behavioral theory of the firm (BTOF), this study attempts to present a more refined model on the relationship between the two. The results in this study reveal that as firms’ performance rises further above their aspiration level, they are less likely to show better CSR performances and are also less likely to avoid taxes. Firms performing just above their aspiration level show higher CSR performances and firms performing nearby (both below and above) their aspiration level avoid more taxes. In conclusion, firms’ CSR and tax payment decisions are related to the desire to meet or beat an aspiration level or sustain competitive advantage than being ethical or unethical. JEL CLASSIFICATION M14; H26


Author(s):  
Carlos Salavera ◽  
Pablo Usán

This study examines the relationship between social skills and happiness in 1st-year Teaching School students, as well as possible gender differences. The sample comprised 243 Teaching School students (Primary Education) in Zaragoza, including 110 men (45.27%) and 133 women (54.73%), aged 18–25 (average age 20.23 years; s.d. = 1.586). In order to analyse the relationship between social skills and subjective happiness, the Scale of Social Skills and Subjective Happiness Scale were used. While men scored higher in all social skills-related factors, women scored higher in all factors related to happiness. The study shows that factors such as self-expression in social settings and the ability to say no and cut off social interactions have a direct and significant effect on happiness among men, while self-expression in social settings and the ability to express anger led to a higher perception of happiness among women. Similarly, situations such as asking for and defending rights have an indirect and significant effect in men, reducing their levels of happiness. In the case of women, no social skills factors were found that led to lower happiness. It may be concluded that significant gender differences exist, although broader and lateral studies are needed in order to examine the relationship between gender identities, social skills and subjective happiness more in depth, and thus, understand the effect of these constructs in the development of personality.


2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 65-65
Author(s):  
Yeonji Ryou ◽  
Ryou Yeonji

Abstract The purpose of this study is to identify the trend of the employment status in 65 years or older adults who reside in South Korea and to explore the relationship between the status of employment and individual and family-related factors. This study utilized 10-year and 6-wave secondary data from the Korean Longitudinal Study of Ageing (KLoSA). The original panel sample is a random sample of 10,254 adults who are 45 or older, but for the aim of this study, the participants younger than 65 years were excluded. The number of samples in each wave is different, ranging from 4,013 to 4,335 due to the death of the participant, the rejection of additional interviews, and the refreshment participant collected in Wave 5. The findings indicate that the absolute employment of the people aged 65 or older and the proportion of working people among those have increased over the past decade. In this study, it is also found that there is a close relationship between employment status and individual factors such as gender, educational background, health condition, region, etc. Moreover, the results suggest that there are various facets of the relationship between employment status and family-related factors including whether living with children, the number of the member whom I help with daily activities, the total amount of financial support from/to children/parents/other family or whether participating social activities, etc. The implications of the need for employing the older population and the consideration family-related factors in the policy-making process in Korea are discussed.


2021 ◽  
Vol 80 (1) ◽  
Author(s):  
Waleed Alghamdi ◽  
Godwin O. Ovenseri-Ogbomo

Background: Visual impairment is disproportionately distributed between rural and urban dwellers. Rural dwellers have limited access to the eye care services that are available in urban cities.Aim: The aim of this study was to determine the prevalence and causes of visual impairment in Dariyah, a rural community in the Qassim region, Saudi Arabia.Setting: This research comprised a population-based assessment of the vision and visual status of the inhabitants of Dariyah community.Methods: A cross-sectional descriptive study was conducted amongst the inhabitants of the community of Dariyah. A comprehensive eye examination consisting of visual acuity, ocular health examination, objective and subjective refraction was performed. The examinations were conducted by registered ophthalmologists and optometrists from the Qassim University. Vision impairments were categorised according to the International Classification of Diseases (ICD), Section 9D90, ‘Vision impairment including blindness’ (2018).Results: In all, 68 (24.5%) participants had vision impairment (using the better-seeing eye), with refractive errors being the main cause of vision impairment. Other causes of vision impairment included cataract (20, 7.2%), trichiasis (5, 1.8%) and glaucoma (2, 0.7%). Refractive errors were present in 193 (69.7%), with astigmatism being the commonest refractive error. About 60% of those with refractive errors presented without spectacles for correction, and 20% reported that they had never had an eye examination. Refractive errors could not be determined in 19 (6.9%) of the subjects because of conditions such as matured cataract and other ocular abnormalities.Conclusion: Uncorrected refractive error was found to be the leading cause of vision impairment in this rural community in Saudi Arabia.


2021 ◽  
pp. 1-59
Author(s):  
Caihong Wen ◽  
Arun Kumar ◽  
Michelle L’ Heureux ◽  
Yan Xue ◽  
Emily Becker

AbstractThe relationship between the Warm Water Volume (WWV) ENSO precursor and ENSO SST weakened substantially after ~2000, coinciding with a degradation in dynamical model ENSO prediction skill. It is important to understand the drivers of the equatorial thermocline temperature variations and their linkage to ENSO onsets. In this study, a set of ocean reanalyses is employed to assess factors responsible for the variation of the equatorial Pacific Ocean thermocline during 1982-2019. Off-equatorial thermocline temperature anomalies carried equatorward by the mean meridional currents associated with Pacific Tropical Cells are shown to play an important role in modulating the central equatorial thermocline variations, which is rarely discussed in the literature. Further, ENSO events are delineated into two groups based on precursor mechanisms: the western equatorial type (WEP) ENSO, when the central equatorial thermocline is mainly influenced by the zonal propagation of anomalies from the western Pacific, and the off-equatorial central Pacific (OCP) ENSO, when off-equatorial central thermocline anomalies play the primary role. WWV is found to precede all WEP ENSO by 6-9 months, while the correlation is substantially lower for OCP ENSO events. In contrast, the central tropical Pacific (CTP) precursor, which includes off-equatorial thermocline signals, has a very robust lead correlation with the OCP ENSO. Most OCP ENSO events are found to follow the same ENSO conditions, and the number of OCP ENSO increases substantially since the 21st century. These results highlight the importance of monitoring off-equatorial subsurface preconditions for ENSO prediction and to understand multi-year ENSO.


2021 ◽  
Author(s):  
Freek Van Baelen ◽  
Melissa De Regge ◽  
Bart Larivière ◽  
Katrien Verleye ◽  
Sam Schelfout ◽  
...  

BACKGROUND Last decade has shown a considerable increase in the amount of mobile health applications (mHealth apps) in everyday life. These mHealth apps have the potential to significantly improve well-being for chronically ill patients. However, behavioral engagement with mHealth apps remains low. OBJECTIVE The aim of this study is to provide insight into the behavioral engagement of adults with chronic conditions with mHealth apps by investigating (1) how it is affected by human-related factors (here, physician motivation) and app-related factors (here, app integration) and (2) how it affects their well-being. Supplementary, this study considers the moderating effect of preference for traditional visits to the physician (habit) and experience in app use (app experience) by the patients. METHODS A scenario based experiment among patients with a chronic condition (n= 521) was carried out. A Bayesian SEM model with mediation and moderation analysis was conducted in MPlus. RESULTS Both physician motivation for mHealth app use and mHealth app integration have a positive effect on the behavioral engagement of chronically ill patients towards mHealth apps. Higher behavioral engagement positively influences the hedonic and eudaimonic well-being of chronically ill patients. App experience positively moderates the relationship between app integration and behavioral engagement. A patients’ habit with receiving traditional care does not moderate the relationship between physician motivation and behavioral engagement. CONCLUSIONS The human and design factor play a key role in behavioral engagement and well-being among patients with a chronic condition. During and after the development of a mHealth app, app integration and physician motivation should be a point of attention.


2012 ◽  
Vol 2 (6) ◽  
pp. 22
Author(s):  
Georgia Stephanou ◽  
Georgios Gkavras

This study study aimed to examine (a) adolescents’ attributions and emotions for their subjectively perceived good and bad relationships with their parents, (b) the association of the intuitive and attributional appraisals of the adolescent-parent relationship with the subsequent emotions, and (c) the role of the perceived importance of the good adolescent-parent relationship in the generation of attributions and emotions, and in the impact of attributions on emotions. The sample comprised 670 adolescents, both genders, aged 14-17 years old, representing various parental socioeconomic levels. The results showed that: (a) It was extremely important for the adolescents to have good relationships with their parents, (b) the perceived good adolescent-parent relationships were attributed to internal, stable and personal controllable factors, along with parent- and self-parent interactive- related factors, while the estimated as bad relationships were attributed to external, stable, personal uncontrollable and external controllable factors (parents’ negative properties), (c) the adolescents experienced intense positive and negative emotions (mainly, general / outcome- dependent) for the perceived good and bad relationships with their parents, respectively, (d) both intuitive and attributional appraisals of the relationship were associated with the emotions, particularly in the perceived bad adolescent-parent relationship, and (e) the relative strength of the association of the attributional dimensions with the emotions varied between the perceived good and bad adolescent-parent relationship and across the various emotions. Keywords: Adolescent-Parent Relationship, Attributions, Emotions, Intuitive Appraisal.


2002 ◽  
Vol 11 (2) ◽  
pp. 71-75
Author(s):  
Machiko Endo ◽  
Kaori Tsunematsu ◽  
Katsura Ishizu ◽  
Syoichi Ishizaki ◽  
Hitoshi Ishizaka

Sign in / Sign up

Export Citation Format

Share Document