Hormone Replacement Therapy and Dry Eye in Post Menopausal Women: Study in a Tertiary Centre in Malaysia

Background: Menopause involves decrease in the body estrogen level. There are many disorders associated with estrogen deficiency state. Postmenopausal women frequently report dry eye symptoms due to the decrease in the level of circulating estrogen hormone. Hormone replacement therapy (HRT) is given to alleviate some of the menopausal effects. This study aimed to compare the tear production between postmenopausal women treated with or without HRT.Methods: This cross-sectional study was performed on 140 participants attending various clinics in Universiti Kebangsaan Malaysia Medical Centre (UKMMC) namely the obstetric and gynecology, Surgery, Orthopedic and Otorhinolaryngology clinics over a period of 3 months. The subjects were either with or without HRT. Schirmer’s Test strip was used to measure the tear quantity. Dry eye was defined when the length of the moistened area on the strip is less than 5 mm.Results: The results showed significant difference in tear quantity in postmenopausal women treated with or without HRT (p=0.003). No correlation was observed between tear quantity and duration of HRT consumption (p=0.217). No significant correlation was also found between the tear quantity and duration of menopause (p=0.150).Conclusions: Our results suggested that HRT helps in improving tear production in postmenopausal women regardless of the duration of HRT consumption or menopause. However, duration of HRT consumption or menopause exert no significant effect on the tear quantity

The Arctic in the twenty-first century: changing biogeochemical linkages across a paraglacial landscape of Greenland

The Kangerlussuaq area of southwest Greenland encompasses diverse ecological, geomorphic, and climate gradients that function over a range of spatial and temporal scales. Ecosystems range from the microbial communities on the ice sheet and moisture-stressed terrestrial vegetation (and their associated herbivores) to freshwater and oligosaline lakes. These ecosystems are linked by a dynamic glacio-fluvial-aeolian geomorphic system that transports water, geological material, organic carbon and nutrients from the glacier surface to adjacent terrestrial and aquatic systems. This paraglacial system is now subject to substantial change because of rapid regional warming since 2000. Here, we describe changes in the eco- and geomorphic systems at a range of timescales and explore rapid future change in the links that integrate these systems. We highlight the importance of cross-system subsidies at the landscape scale and, importantly, how these might change in the near future as the Arctic is expected to continue to warm

Design, Development and Experiment Analysis of Solar Panel Cleaning System

As the world moves towards a greener future, adoption of renewable energy sources has become very popular and solar power has become one of the most desirable sources of energy. The performance and efficiency of solar panel modules are very much affected by environmental parameters such as temperature, irradiance and dust. Many studies found that the accumulation of dust on the surface of solar panels has seriously reduced the output power of a solar panel. Dust that has accumulated on the panels may reflect or refract the photons thus preventing them from reaching the surface of the panel. Thus, it has reduced the efficiency of solar panels by 3–25%. This study aims to design and fabricate a solar panel cleaning system. The system will be placed atop the solar panels. It consists of an on-board cleaning brush, water tank and control electronics. After the fabrication of the design, testing is done using an acrylic panel embedded with LDR sensors. The intensity of the light passing through the panel is measured before and after multiple cleaning passes. Based on the results, the cleanliness of the surface had significantly improved the efficiency of the panel from 60 to 98% after 3 cleaning passes using water jet

Consequences of grazer‐induced vegetation transitions on ecosystem carbon storage in the tundra

Large herbivores can control plant community composition and, under certain conditions, even induce vegetation shifts to alternative ecosystem states. As different plant assemblages maintain contrasting carbon (C) cycling patterns, herbivores have the potential to alter C sequestration at regional scales. Their influence is of particular interest in the Arctic tundra, where a large share of the world's soil C reservoir is stored. We assessed the influence of grazing mammals on tundra vegetation and C stocks by resampling two sites located along pasture rotation fences in northern Norway. These fences have separated lightly grazed areas from heavily grazed areas (in close proximity to the fences) and moderately grazed areas (further away from the fences) for the past 50 years. Fourteen years earlier, the lightly and moderately grazed areas were dominated by dwarf shrubs, whereas heavy grazing had promoted the establishment of graminoid-dominated vegetation. Since then, both reindeer densities and temperatures have increased, and more time has passed for transient dynamics to be expressed. We expected that the vegetation and C stocks would have changed under all grazing intensities, but not necessarily in the same way. At the site where relative reindeer numbers and trampling intensity had increased the most, graminoid-dominated vegetation was now also found in the moderately grazed area. At the other site, the dominant vegetation types under all grazing intensities were the same as 14 years earlier. We show that the heavily grazed, graminoid-dominated areas stored less C above-ground than the lightly grazed, shrub-dominated areas. Yet, the below-ground consequences of grazing-induced grassification varied between the sites: Grazing did not alter organic soil C stocks at the site where both evergreen and deciduous shrubs were abundant in the lightly grazed area, whereas heavy grazing increased organic soil C stocks at the site where the deciduous shrub Betula nana was dominant. Our results indicate that, despite the negative impacts of grazers on above-ground C storage, their impact on below-ground C may even be positive. We suggest that the site-specific responses of organic soil C stocks to grazing could be explained by the differences in vegetation under light grazing. This would imply that the replacement of deciduous shrubs by graminoids, as a consequence of grazing could be beneficial for C sequestration in tundra soils. A plain language summary is available for this article