An 85-year-old Woman with Altered Mental Status and Hypotension

An 85-year-old female patient was brought to emergency department (ED) from a nursing home with altered mental status (GCS: 12/15) and hypotension (90/60 mmHg). Bilateral fine crackles in lungs and severe cachexia were obvious in her physical examination. The ECG showed only sinus tachycardia. Several attempts at peripheral vein cannulation failed due to poor visualization of severely atrophied and contracted subcutaneous veins. Therefore, on two attempts, a central venous catheter (CVC) was inserted into the right internal jugular vein (IJV) using the Seldinger technique. After securing and taping the central line, fluid infusion started with no difficulty and a portable chest x-ray was ordered

Spatial-Temporal Simulation of LAI on Basis of Rainfall and Growing Degree Days

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).The dimensionless Leaf Area Index (LAI) is widely used to characterize vegetation cover. With recent remote sensing developments LAI is available for large areas, although not continuous. However, in practice, continuous spatial-temporal LAI datasets are required for many environmental models. We investigate the relationship between LAI and climatic variable rainfall and Growing Degree Days (GDD) on the basis of data of a cold semi-arid region in Southwest Iran. For this purpose, monthly rainfall and temperature data were collected from ground stations between 2003 and 2015; LAI data were obtained from MODIS for the same period. The best relationship for predicting the monthly LAI values was selected from a set of single- and two-variable candidate models by considering their statistical goodness of fit (correlation coefficients, Nash-Sutcliffe coefficients, Root Mean Square Error and mean absolute error). Although various forms of linear and nonlinear relationships were tested, none showed a statistically meaningful relationship between LAI and rainfall for the study area. However, a two-variable nonlinear function was selected based on an iterative procedure linking rainfall and GDD to the expected LAI. By taking advantage of map algebra tools, this relationship can be used to predict missing LAI data for time series simulations. It is also concluded that the relationship between MODIS LAI and modeled LAI on basis of climatic variables shows a higher correlation for the wet season than for dry season

An 85-year-old Woman with Altered Mental Status and Hypotension

An 85-year-old female patient was brought to emergency department (ED) from a nursing home with altered mental status (GCS: 12/15) and hypotension (90/60 mmHg). Bilateral fine crackles in lungs and severe cachexia were obvious in her physical examination. The ECG showed only sinus tachycardia. Several attempts at peripheral vein cannulation failed due to poor visualization of severely atrophied and contracted subcutaneous veins. Therefore, on two attempts, a central venous catheter (CVC) was inserted into the right internal jugular vein (IJV) using the Seldinger technique. After securing and taping the central line, fluid infusion started with no difficulty and a portable chest x-ray was ordered

Rainfall-runoff modelling using a spatially distributed electrical circuit analogue

© 2016, Springer Science+Business Media Dordrecht. The assessment and prevention of floods require appropriate forecasting and knowledge of the related hydrological processes. Due to the similar form of the governing equations, flood hydrograph shows a clear analytical and mathematical analogy with electrical circuits. In this paper, a spatially distributed hydrological model is developed which is analogue to a network of electrical resistance–capacitance with five circuits for describing the hydrological processes leading to floods. The spatially distributed hydrological model simulates rainfall, potential evapotranspiration, canopy interception, surface storage and soil storage. The parameters for analogical modelling were derived from translation of the physical catchment characteristics. A two-parameter Weibull equation aggregates the response functions of each pixel and calculates the hydrograph of the catchment. We applied the model to the ‘Open-Book’ or ‘tilted V-catchment’ theoretical benchmark problem, as well as to four hourly flood events and simulation of daily discharges. For the last two cases, data were used from the mountainous catchment of upper Tarqui in the Andes of Ecuador. Comparison of single versus multiple circuit designs for the benchmark problem indicates that the multiple circuit analogy provides a result similar to other hydrological models. The results further illustrate the usefulness of the methodology for flood modelling and how it can simplify the simulation for ungauged basins of temporal and spatial variations of influencing hydrological processes.status: publishe

Spatiotemporal variation of water balance components in Mashhad catchment, Iran: Investigating the impact of changes in climatic data and land use

The research aims to investigate the spatiotemporal changes in water balance components and distinguish the relative impacts of climatic data and land-use on groundwater levels in northeastern Iran. This investigation employs the WetSpass-M model to estimate water balance and the Mann-Kendall test alongside Sen's slope estimator to evaluate the trend. The study also assesses mean annual water balance components, considering diverse combinations of land use and soil. The findings offer a hydrological insight revealing that 14% of precipitation results in runoff, 29% of that recharging the aquifer; the remaining portion is lost through evapotranspiration. The trends in precipitation and simulated water components are not significant but a significant downward trend in groundwater is observed beyond a specific point in time. Based on this outcome, as well as the analysis of land-use changes, it was speculated that human activities in this fast-developing region might be implicated in the decline in groundwater levels. Analysis of water balance components in various soil and land-use combinations indicates that evapotranspiration exhibits greater variability within the land-cover class, while recharge is more influenced by soil texture. These findings enhance our understanding of identifying potential sites for artificial recharge and determining sustainable groundwater withdrawals based on spatiotemporal recharge patterns

Investigating spatial and temporal trend of groundwater quality in relation to water balance in 2007–2017: a case study of Chaharmahal va Bakhtiari Province, Iran

Abstract The extensive exploitation of water resources in Chaharmahal va Bakhtiari province has led to a destructive impact on the water balance and quality of the region. In order to evaluate water quality of the study area, water quality parameters from 132 wells were analyzed to prepare spatial distribution maps of the IRWQI index. To analyze spatial and temporal rainfall anomalies, the SPI index was spatially interpolated using the ordinary Kriging method. Principal component analysis was used to investigate the relationship between water quality parameters. The suitability of data for PCA was evaluated by the Kaiser–Meyer–Olkin and Bartlett tests. Additionally, water balance components of the study area, including surface runoff and ground water, were simulated using the WetSpass-M model. According to the results of the IRWQI index, 54 wells, mostly located in built-up and agricultural lands, had poor quality․ Investigation of the average groundwater quality during the years 2007 to 2017 shows that the trend of groundwater quality decreased. Comparison of drought and water quality maps showed similar patterns so that in areas with extreme drought, water quality was bad. The highest and lowest recorded concentrations for nitrates were related to built-up and rangeland lands with concentrations of 35 and 21 mg/l, respectively. Comparison among land use classes showed that in the rangelands, groundwater quality was better and nitrate level was lower compared to agricultural and built-up areas. Overall, the results of this study show that water quality can be affected by land use types and water balance components

A distributed monthly water balance model: formulation and application on Black Volta Basin

© 2017, Springer-Verlag Berlin Heidelberg. Recharge assessment is of critical importance for groundwater resources evaluation in arid/semiarid areas, as these have typically limited surface water resources. There are several models for water balance evaluation. One of them is WetSpass, which has the ability to simulate spatially distributed recharge, surface runoff, and evapotranspiration for seasonally averaged conditions. This paper presents a modified methodology and model, WetSpass-M, in which the seasonal resolution is downscaled to a monthly scale. A generalized runoff coefficient was introduced, enabling runoff estimation for different land-use classes. WetSpass-M has been calibrated and validated with observed streamflow records from Black Volta. Base-flow from simulated recharge was compared with base-flow derived via a digital filter applied to the observed streamflow and has shown to be in agreement. Previous studies have concluded that for this basin, small changes in rainfall could cause a large change in surface runoff, and here a similar behavior is observed for recharge rates. An advantage of the new model is that it is applicable to medium- and large-sized catchments. It is useful as an assessment tool for evaluating the response of hydrological processes to the changes in associated hydrological variables. Since monthly data for streamflow and climatic variables are widely available, this new model has the potential to be used in regions where data availability at high temporal resolution is an issue. The spatial–temporal characteristics of the model allow distributed quantification of water balance components by taking advantage of remote sensing data.status: publishe

Biomass Burning and Water Balance Dynamics in the Lake Chad Basin in Africa

The present study investigated the effect of biomass burning on the water cycle using a case study of the Chari–Logone Catchment of the Lake Chad Basin (LCB). The Chari–Logone catchment was selected because it supplies over 90% of the water input to the lake, which is the largest basin in central Africa. Two water balance simulations, one considering burning and one without, were compared from the years 2003 to 2011. For a more comprehensive assessment of the effects of burning, albedo change, which has been shown to have a significant impact on a number of environmental factors, was used as a model input for calculating potential evapotranspiration (ET). Analysis of the burning scenario showed that burning grassland, which comprises almost 75% of the total Chari–Logone land cover, causes increased ET and runoff during the dry season (November–March). Recent studies have demonstrated that there is an increasing trend in the LCB of converting shrubland, grassland, and wetlands to cropland. This change from grassland to cropland has the potential to decrease the amount of water available to water bodies during the winter. All vegetative classes in a burning scenario showed a decrease in ET during the wet season. Although a decrease in annual precipitation in global circulation processes such as the El Niño Southern Oscillation would cause droughts and induce wildfires in the Sahel, the present study shows that a decrease in ET by the human-induced burning would cause a severe decrease in precipitation as well