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Exploring the impacts of CO2 and soil water availability on the photosynthetic performance and water use efficiency of three green manure plants could provide theoretical basis for the adaptive management of grassland ecosystems under future climate change. An experiment was conducted in an artificial climate chamber with precisely controled CO2 concentrations of 400 (natural atmospheric) and 800 µmol · mol-1 (doubled), and four water treatments, 80% field water holding capacity (FC) (full irrigation control group), 55%-60% FC (mild water deficit), 35%-40% FC (moderate water deficit), <35% FC (severe water deficit) to investigate the impacts of increasing CO2 concentration and water deficit on chlorophyll content, gas exchange variables, and water use efficiency (WUE) of oilseed rape (Brassica napus), white clover (Trifolium repens), and alfalfa (Medicago sativa). The results showed that under the same CO2 concentration, when soil moisture was less than 40% FC, the chlorophyll content and gas exchange parameters of three plants were significantly decreased. The treatment of 55%-60% FC did not alter the total chlorophyll content of three species, but reduced the photosynthetic rate (Pn) and transpiration rate (Tr) of white clover and alfalfa by 6%-25% and did not affect their WUE. Compared with atmospheric CO2 concentration, the doubled CO2 concentration significantly decreased the Pn of oilseed rape by 21.5% under the full irrigation treatment, increased the Pn of three species under mild water deficit, increased the Pn of oilseed rape and alfalfa under moderate water deficit, but only improved the Pn of alialfa under severe water deficit. The doubled CO2 concentration significantly increased WUE of white clover and alfalfa under all water deficit conditions, but only increased WUE of oilseed rape under mild water deficit. Increasing CO2 concentration and water deficit significantly interacted to affect Pn of three species and the WUE of oilseed rape. In summary, the three species differed in their responses to doubled atmospheric CO2 concentration and different levels of water deficit. Our results suggested that elevated CO2 concentration could improve the adverse effects of mild water deficit on photosynthetic performance and WUE of three species, but only improve the photosynthetic performance of alfalfa under severe water deficit. [ABSTRACT FROM AUTHOR]

Background: The population of elderly patients with gastric cancer is increasing, which is a major public health issue in China. Malnutrition is one of the greatest risk factors for adverse clinical outcomes in elderly patients with gastric cancer., Aim: To investigate the preoperative nutritional status and its association with delayed discharge of elderly gastric cancer patients following radical gastrectomy., Methods: A total of 783 patients aged 65 years and older harboring gastric adenocarcinoma and following radical gastrectomy were retrospectively analyzed from the prospectively collected database of Zhongshan Hospital of Fudan University between January 2018 and May 2020., Results: The overall rate of malnutrition was 31.8%. The incidence of postoperative complications was significantly higher in the malnourished group compared to the well-nourished group ( P < 0.001). Nutritional characteristics in the malnourished group, including body mass index, prognostic nutritional index (PNI), albumin, prealbumin, and hemoglobin, were all significantly lower than those in the well-nourished group. The percentage of patients who received postoperative total nutrient admixture was lower in the malnourished group compared to the well-nourished group (22.1% vs 33.5%, P = 0.001). Age ≥ 70 years (HR = 1.216, 95%CI: 1.048-1.411), PNI < 44.5 (HR = 1.792, 95%CI: 1.058-3.032), operation time ≥ 160 minutes (HR = 1.431, 95%CI: 1.237-1.656), and postoperative complications grade III or higher (HR = 2.191, 95%CI: 1.604-2.991) were all recognized as independent risk factors associated with delayed discharge., Conclusion: Malnutrition is relatively common in elderly patients undergoing gastrectomy. Low PNI is an independent risk factor associated with delay discharge. More strategies are needed to improve the clinical outcome of these patients., Competing Interests: Conflict-of-interest statement: The authors claim no conflict of interests., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

To clarify the desiccation effect of deep soil and water footprint of crop production in two typical dry-farming apple orchards on the Loess Plateau of China, with Luochuan County in semi-humid region and Mizhi County in semi-arid region as two typical apple planting areas, we used the WinEPIC model to quantitatively simulate and analyze the variations of soil moisture from 0 to 15 m and water footprint of apple production during 1980-2020. The results showed that annual yield of mature orchards in Luochuan and Mizhi followed an "S" curve, with the average annual values being 24.64 and 18.42 t·hm -2 , respectively. The average annual evapotranspirations of Luochuan and Mizhi were 623.82 and 458.97 mm, the average annual drought stress days of Luochuan and Mizhi were 20.4 and 52.73 days, and the water overconsumption were 167.94 and 121.15 mm, respectively. The available soil water contents in Luochuan and Mizhi showed a sharp decline from 1 to 25 years old and from 1 to 23 years old, respectively, with average annual soil desiccation rates being 64.6 and 68.03 mm·a -1 , respectively. The dry layer of deep soil for the orchards of Luochuan and Mizhi appeared at the 13th and 7th years, and would be stable after 23 and 22 years, respectively. The formation and stability time of the soil dry layer in the area with high precipita-tion was later than that with low precipitation. Long-term soil moisture deficit would result in irreversible soil dry layer. Water footprint of apple production in Luochuan and Mizhi were low in the early stage and high in the later stage, with the average annual values being 0.187 and 0.194 m 3 ·kg -1 , respectively. Both apple yield and production water footprint were affected by precipitation. To ensure the sustainable and healthy development of apple industry, it was recommended that the optimal planting age of apple trees is about 23 years on the Loess Plateau where water sources is limited, and the maximum should not exceed 25 years.

In recent decades, extreme climate occurred frequently on the Loess Plateau. It is thus particularly important to study and predict the occurrence of extreme climate. Available researches on extreme climate mainly focus on the changing characteristics of the event itself, but ignore the correlation between average temperature and its changing trend. We used linear trend estimation, Mann-Kendall test, sliding t test and Pearson correlation analy-sis to study the variation trend of extreme temperature and its correlation with average temperature on the Loess Plateau based on the daily maximum temperature, minimum temperature and average temperature data of 79 meteo-rological stations from 1986 to 2019. The results showed that the extreme warmth index in the Loess Plateau region showed a significant upward trend, the extreme cold index showed a significant downward trend, and the frequency of extreme high temperature events increased. Most of the extreme temperature indices had abrupt changes in the middle and late 1990s and in 2012, and the extreme temperature showed a downward trend from 1998 to 2012, which better responded to the phenomenon of global warming hiatus. The increasing trend of mean temperature in the gully region, the rocky mountain region and the valley plain region was more obvious than that in other regions. The stations with large trend of extreme temperature index almost all occurred in the region with large increases of mean temperature. The increases of average temperature in small increments increased the frequency of extreme high temperature event, with the change range of extreme low temperature and its rate being greater than the extreme high temperature. Climate warming on extreme temperature index had a different effect, small changes in the average temperature in the Loess Plateau made the climate transfer towards the direction of more frequent heat.

Exploring the impacts of CO 2 and soil water availability on the photosynthetic performance and water use efficiency of three green manure plants could provide theoretical basis for the adaptive management of grassland ecosystems under future climate change. An experiment was conducted in an artificial climate chamber with precisely controled CO 2 concentrations of 400 (natural atmospheric) and 800 μmol·mol -1 (doubled), and four water treatments, 80% field water holding capacity (FC) (full irrigation control group), 55%-60% FC (mild water deficit), 35%-40% FC (moderate water deficit), &lt;35% FC (severe water deficit) to investigate the impacts of increasing CO 2 concentration and water deficit on chlorophyll content, gas exchange variables, and water use efficiency (WUE) of oilseed rape ( Brassica napus ), white clover ( Trifolium repens ), and alfalfa ( Medicago sativa ). The results showed that under the same CO 2 concentration, when soil moisture was less than 40% FC, the chlorophyll content and gas exchange parameters of three plants were significantly decreased. The treatment of 55%-60% FC did not alter the total chlorophyll content of three species, but reduced the photosynthetic rate ( P n ) and transpiration rate ( T r ) of white clover and alfalfa by 6%-25% and did not affect their WUE. Compared with atmospheric CO 2 concentration, the doubled CO 2 concentration significantly decreased the P n of oilseed rape by 21.5% under the full irrigation treatment, increased the P n of three species under mild water deficit, increased the P n of oilseed rape and alfalfa under moderate water deficit, but only improved the P n of alfalfa under severe water deficit. The doubled CO 2 concentration significantly increased WUE of white clover and alfalfa under all water deficit conditions, but only increased WUE of oilseed rape under mild water deficit. Increasing CO 2 concentration and water deficit significantly interacted to affect P n of three species and the WUE of oilseed rape. In summary, the three species differed in their responses to doubled atmospheric CO 2 concentration and different levels of water deficit. Our results suggested that elevated CO 2 concentration could improve the adverse effects of mild water deficit on photosynthetic performance and WUE of three species, but only improve the photosynthetic performance of alfalfa under severe water deficit.