Effective refractive error coverage in adults aged 50 years and older: estimates from population-based surveys in 61 countries.

BACKGROUND: In 2021, WHO Member States endorsed a global target of a 40-percentage-point increase in effective refractive error coverage (eREC; with a 6/12 visual acuity threshold) by 2030. This study models global and regional estimates of eREC as a baseline for the WHO initiative. METHODS: The Vision Loss Expert Group analysed data from 565 448 participants of 169 population-based eye surveys conducted since 2000 to calculate eREC (met need/[met need + undermet need + unmet need]). A binary logistic regression model was used to estimate eREC by Global Burden of Disease (GBD) Study super region among adults aged 50 years and older. FINDINGS: In 2021, distance eREC was 79·1% (95% CI 72·4-85·0) in the high-income super region; 62·1% (54·7-68·8) in north Africa and Middle East; 49·5% (45·0-54·0) in central Europe, eastern Europe, and central Asia; 40·0% (31·7-48·2) in southeast Asia, east Asia, and Oceania; 34·5% (29·4-40·0) in Latin America and the Caribbean; 9·0% (6·5-12·0) in south Asia; and 5·7% (3·1-9·0) in sub-Saharan Africa. eREC was higher in men and reduced with increasing age. Global distance eREC increased from 2000 to 2021 by 19·0%. Global near vision eREC for 2021 was 20·5% (95% CI 17·8-24·4). INTERPRETATION: Over the past 20 years, distance eREC has increased in each super region yet the WHO target will require substantial improvements in quantity and quality of refractive services in particular for near vision impairment. FUNDING: WHO, Sightsavers, The Fred Hollows Foundation, Fondation Thea, Brien Holden Vision Institute, Lions Clubs International Foundation.

Coupling Effects of Nitrogen and Irrigation Levels on Growth Attributes, Nitrogen Use Efficiency, and Economics of Cotton.

Nitrogen (N) fertilization plays a pivotal role in physiomorphological attributes and yield formation of field-grown cotton (Gossypium hirsutum L.), but little is known of its interaction with irrigation levels. Therefore, this study was conducted with an objective of evaluating the impact of irrigation and nitrogen levels on growth attributes and nitrogen use efficiency of Bt cotton (Gossypium spp.) in the hot arid region. The experiment consisted of a factorial arrangement of three irrigation levels (200, 400, and 600 mm) and four nitrogen rates (0, 75, 150, and 225 kg ha-1) in a split-plot design with three replications. Nitrogen fertilization and irrigation levels influenced cotton growth attributes and yield. The highest leaf area index, dry matter accumulation, crop growth rate, and relative growth rate were achieved at 225 kg N ha-1 and irrigation level 600 mm as compared to other experimental treatments. Similarly, nitrogen uptake and content by seed, lint, and stalk and total nitrogen uptake recorded maximum at 225 kg N ha-1 and irrigation level 600 mm. Interestingly, the treatment of 600 mm of irrigation and 150 kg N ha-1 displayed significant increase in nitrogen use efficiency indices such as agronomic efficiency of nitrogen (AEN) and recovery efficiency of nitrogen (REN), while partial factor productivity of nitrogen (PFPN) and internal nitrogen use efficiency (iNUE) were significantly higher with application of 600 mm of irrigation and nitrogen application rate of 75 kg ha-1. Application of 600 mm of irrigation along with 225 kg N ha-1 resulted in significant increase in gross return, net return, and B:C ratio than any other treatment combinations. So, application of 600 mm of irrigation along with 225 kg N ha-1 could be recommended for achieving higher growth and yield, as well as profitability of Bt cotton under hot arid region and similar agroecologies.

Intraocular pressure and associated factors: the central India eye and medical study.

PURPOSE: To determine the range of intraocular pressure (IOP) in a rural Central Indian population and to evaluate existing and identify potential new ocular, medical, and socioeconomic factors associated with IOP. METHODS: This is a population-based study carried out in Nagpur in Central India. A single IOP measurement was taken using Goldmann applanation tonometry and population IOP was described using standard descriptive statistics. RESULTS: Of 5885 eligible patients, 9338 eyes of 4686 patients were included in the study. The mean IOP was 13.6±3.4 mm Hg (median: 14 mm Hg; range: 2 to 56 mm Hg). In multivariate regression analysis, the following factors, with correlation coefficients (r) and P values reported in parenthesis, were found to be associated with IOP. Ocular factors included higher corneal power (0.12; P=0.004), lower central corneal thickness (0.02; P<0.001), and higher myopic refractive power (-0.13; P=0.001). Medical factors included diastolic blood pressure (0.05; P<0.001), pulse rate (0.02; P=0.005), and body mass index (0.05; P=0.01). Socioeconomic factors included level of education (0.15; P=0.05) and livestock ownership (-0.18; P=0.008). CONCLUSION: Low mean IOP was found when compared with other epidemiologic studies and this may be explained by the low central corneal thickness found in the study population. Several known ocular and medical factors and new socioeconomic factors were found to be associated with IOP. Identifying risk factors associated with IOP in different populations may allow clinicians to better define and recognize subgroups of patients at risk of elevated IOP. Newly identified socioeconomic-IOP associations will need to be validated in future studies.