PMC

Simple representation of a river section where a city extracts its municipal water from (gross water abstraction A). Part from this water is “lost” from the river as consumptive water use B (net water abstraction) and part is returned (after treatment in a wastewater treatment plant or WWTP) downstream as return flow (A–B). Between the upstream gross water abstraction and downstream return flow, the river flow Q receives a hydrological surplus of Q₁. This river section is however deprived of the quantity A (which makes a WS indicator using gross water abstraction relevant). Downstream of the return flow, the river is only deprived of the quantity B (which makes a WS indicator using net water consumption relevant).

Linear mixed-effects models were used to determine the association between momentary awareness of daily water intake goals on a Likert scale and daily water intake. Models included a random intercept for each patient and adjusted for age, sex, weekday indicator, time of prompt (morning, noon, afternoon, evening), and prior kidney stone passage or surgery. We assumed every participant always responded affirmatively to each level of agreement with the statement: “I know how much water I am supposed to drink today.” to estimate daily water intake, proportion of daily water goal met, and proportion of participants who met the daily water goal ≥4 days. The histograms represent the frequency of estimated daily water intake volume for each level of agreement. The reported differences and p-values reflect comparisons of estimated daily water intake for each level of agreement with “disagree”

Linear mixed-effects models were used to determine the association between momentary awareness of water intake volume on a Likert scale and daily water intake. Models included a random intercept for each patient and adjusted for age, sex, weekday indicator, time of prompt (morning, noon, afternoon, evening), and prior kidney stone passage or surgery. We assumed every participant always responded affirmatively to each level of agreement with the statement: “I know how many glasses of water I have drunk today (or how many bottles of HidrateSpark I have drunk today.” to estimate daily water intake, proportion of daily water goal met, and proportion of participants who met the daily water goal ≥4 days. The histograms represent the frequency of estimated daily water intake volume for each level of agreement. The reported differences and p-values reflect comparisons of estimated daily water intake for each level of agreement with “disagree”.

Schematic representation of the experimental apparatus. Adsorption breakthrough experiments were performed upward through the column, while desorption was from top to bottom. DCM was fed from the “Wet DCM” vessel during the adsorption cycles, while regeneration was performed by pumping and evaporating dry DCM. Both desorbed water and DCM were condensed after the bed and collected in the “Wet DCM” vessel during the desorption cycle. The amount of water desorbed was quantified with the through flow graduated cylinder, in which water accumulated while DCM passed through, due to density difference. Water content of DCM exiting the graduated cylinder was measured by Karl Fischer titration to close the water mass balance. Legend: LI, level indicator; FC, mass flow controller; PI, pressure indicator; TI, temperature indicator; and TC, temperature controller.