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Renewable energies have gained momentum in energy transition agenda based on the benefit of lower emissions of carbon and its compounds. Many technologies have been developed at different technology readiness levels addressing climate change impact with reduced emissions of greenhouse gases such as CO2. Herein the perspective article, we have reviewed CO2 capture technologies, such as absorption, adsorption, membrane separation, cryogenic separation and separation via hydrate formation, with further focus on the possibility of utilising ocean thermal energy conversion (OTEC) power to generate green hydrogen and produce low carbon fuels. The potential of OTEC generated hydrogen to produce methanol was explored using a simulation exercise utilising a scenario from a real-life offshore gas production facility. By varying the catalysts and reaction conditions, the findings showed encouraging results of CO2 conversion of ≥50% and product yield of ≥80%. Considering single path reaction with 90%, 95% and 99% of recycling, the highest prediction of methanol production coupled with CO2 hydrogenation process was 276.59 metric tonnes per day (MTPD). In addition, based on the assumption of 13.5 million standard cubic feet per day (MMSCFD) of CO2 produced, 204 MW of OTEC power is required to convert approximately 97.82 MTPD of hydrogen for methanol production making it potentially an industrially viable process. [ABSTRACT FROM AUTHOR]

Purpose: To study optic nerve head (ONH) characteristics using scanning laser ophthalmoscopy, Heidelberg retina tomograph (HRT), in an elderly population. Methods: A population-based, cross-sectional study included 1460 eyes of 1460 consecutive, subjects >60 years, in North India. All subjects underwent a detailed ophthalmic evaluation and imaged on HRT. Stereometric parameters, Moorfields regression analysis (MRA) and discriminant function analysis were analyzed. Correlation between ONH parameters and disc area, age, sex, and intraocular pressure was analyzed. Results: Disc size had a normal Gaussian distribution (2.22 ± 0.48 mm2), but all other stereometric parameters showed a wide variation. MRA found 1320 (90.4%) eyes within normal limits, 71 (4.86%), borderline limits, and 69 (4.73%) outside normal limits. Comparison of eyes meeting International Society of Geographical and Epidemiological Ophthalmology criteria for a glaucoma suspect, C:D > 0.7, with those that did not show a statistically significant difference in the cup area, rim area, rim disc ratio, and cup volume (p = 0.02, 0.02, 0.02, 0.03, respectively). An Intraocular pressure (IOP) ≥21 mmHg was seen in 3.01%, and only 12 eyes out of 1460, 0.82%, had an IOP ≥21 mmHg and a cup:disc ratio of more than 0.7. A van Herick estimation of < Grade 3 was seen in 19.4% Conclusions: Stereometric parameter data, MRA, and clinical examination in this population at high risk for glaucoma found that about 10% of individuals over 60 years of age could be classified as glaucoma suspects and would need further evaluation. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate and compare changes in scanning laser ophthalmoscopy, HRT II, and perimetry in adult primary open angle and chronic angle closure glaucoma over at least five years. Design: Prospective non-randomized clinical trial. Methods: 245 eyes of 245 patients, 116 primary open angle glaucoma, POAG eyes and 129 primary angle closure glaucoma, PACG eyes were studied. Standard achromatic perimetry and optic nerve head topography by HRT II were studied serially, at baseline and thereafter every six months. Results: 14 POAG eyes (11.2%) and 20 PACG eyes (15.5%) showed progression on achromatic perimetry. Kaplan-Meier analysis showed a survival rate of 71% at 148 months for PACG and 86% at 144 months in POAG eyes. Eyes that progressed had frequent records (median 3.08 visits, range 2-10 visits) of a rise of IOP of >4 mm, over the target IOP, during follow-up. In stable eyes, PACG required >50% reduction in IOP to achieve stability on HRT, while POAG eyes showed improvement of optic nerve head parameters even with an IOP reduction of 25%. Conclusion: Intermittent IOP fluctuations of ≥4 mm Hg over the mean IOP was associated with progression in POAG and CPACG eyes. PACG eyes appeared to progress faster and to a greater extent, and were more resistant to changes in ONH tomography following standard therapy, requiring a larger percentage drop in IOP to manifest improvement in optic nerve head parameters, as compared to POAG eyes. [ABSTRACT FROM AUTHOR]