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In the face of global warming, the photosynthesis and transpiration of plants will change greatly, which will ultimately affect the water use efficiency (WUE) of plants. In order to study the coupling effects of CO 2 and temperature on WUE of maize at ear stage, 'Zhengdan 958' was taken as the research object, and 5 temperatures (20 °C, 25 °C, 30 °C, 35 °C and 40 °C) and 11 CO 2 concentration (400, 300, 200, 150, 100, 50, 400, 400, 600, 800 and 1000 μmol mol -1 ) were set to measure the parameters such as net photosynthetic rate ( P n ), transpiration rate ( T r ), stomatal conductance ( G s ) and intercellular CO 2 concentration ( C i ) of single leaves. The response of WUE ( P n / T r ) to CO 2 and temperature was evaluated by a CO 2 response model. The results show that at the same temperature, P n and WUE increased with CO 2 level, while T r decreased as CO 2 level increases; at the same CO 2 concentration, P n and T r were both positively correlated with temperature, while WUE decreased with the increase of temperature. The maximum value of WUE was obtained when the CO 2 concentration was 1000 μmol mol -1 and the temperature was 20.0 °C. The results suggest that global warming will not improve WUE of maize, which will bring more severe challenges to water-saving agriculture and food security., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors. Published by Elsevier Ltd.)

•Wealth attenuated racial differences in self-rated health during young adulthood.•Wealth had consistent incremental effect on health among White & Hispanic Americans.•For Black Americans, wealth was protective of health in the highest wealth quartile.•Individual wealth, not parental wealth was associated with health among Hispanics., (© 2022 The Authors.)