No abstract

The objective of this study is to assess future changes in meteorological, hydrology and agricultural droughts under the impact of changing climate in the Srepok River Basin, a subbasin of LMB, using three drought indices; standardized precipitation index (SPI), standardized runoff index (SRI) and standardized soil moisture index (SSWI). The well-calibrated Soil and Water Assessment Tool (SWAT) is used as a simulation tool to estimate the features of meteorological, hydrological and agricultural droughts. The climate data for the 2016-2040 period is obtained from four different regional climate models; HadGEM3-RA, SNU-MM5, RegCM4 and YSU-RSM, which are downscaled from the HadGEM2-AO GCM. The results show that the severity, duration and frequency of droughts are predicted to increase in the near future for this region. Moreover, the meteorological drought is less sensitive to climate change than the hydrological and agricultural droughts; however, it has a stronger correlation with the hydrological and agricultural droughts as the accumulation period is increased. These findings may be useful for water resources management and future planning for mitigation and adaptation to the climate change impact in the Srepok River Basin.

Background: Orthostatic hypotension (OH) is common in older adults with reported prevalence rates of 5-40%. A direct link between OH and cognitive performance has been proposed due to impaired vascular autoregulation. Aim: To systematically assess the literature of the association between OH and cognitive performance in older adults. Methods: Literature search of MEDLINE, Embase, Cochrane Central Register of Controlled Trials and PsycINFO from inception to May 2017. Studies were included if OH and cognition were assessed in subjects of mean or median age ≥65 years. Risk of bias was assessed with the Newcastle Ottawa Scale. Results: Of 3266 studies screened, 32 studies (22 cross-sectional; 10 longitudinal) reporting data of 28,980 individuals were included. OH prevalence ranged from 3.3% to 58%. Of the 32 studies, 18 reported an association between OH and worse cognitive performance and 14 reported no association. Mini Mental State Examination (MMSE) was the most commonly used cognitive assessment tool. Studies using more than one cognitive assessment tool were more likely to find an association between OH and worse cognition. OH was significantly associated with a lower MMSE mean score (mean difference − 0.51 (95% CI: −0.85, −0.17, p = 0.003)) and an increased risk of cognitive impairment (OR 1.19 (95% CI, 1.00-1.42, p = 0.048)). Conclusions: OH is common in older populations and is associated with worse cognition expressed as lower MMSE scores. Use of MMSE alone as a cognitive assessment tool may underestimate the association. It is yet unclear whether the association between OH and worse cognitive performance is causative.

The effects of climate and land-use changes have put intense pressures on water resources with regard to water quantity and quality in the La Buong River Basin, located in Southern Vietnam. Therefore, an estimate of such effects and their consequences on water resources in this area is needed. The aim of this study is to evaluate the segregated and aggregated effects of climate change and land-use change on streamflow and water quality components (sediment and nutrient loads) using the well-known Soils and Water Assessment Tool (SWAT). The SWAT model was carefully calibrated and validated against the observation data before it can be used as a simulation tool to study the impacts of climate and land-use changes on hydrological processes. As a result of this study, it shows a reduction in the wet-season and annual streamflow, and sediment and nutrient loads will be occurred in the study area due to climate change effects, while the streamflow, and sediment and nutrient loads will be increased under the effects of the land-use change. Moreover, the streamflow and water quality components are more sensitive to land-use change than climate change. The results obtained from this study can provide a basic knowledge of the effects of climate and land-use changes on the streamflow and water quality to the local and national authorities for the future development of integrated water resources management in the La Buong River Basin.