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[ Objective ] Salt stress leads to poor growth and development and decreased ornamental quality of Chinese rose ( Rosa chinensis Jacq. ), and seriously affects their outdoor greening applications in high salt environments or coastal areas. This study explores the effects of exogenous melatonin ( MT ) and inoc- ulation with arbuscular mycorrhizal fungi ( AMF ) on seedling growth , chlorophyll fluorescence parame- ters , and cytokinin metabolism , and analyzes their physiological and the biochemical mechanisms that pro- mote rose to adapt to salt stress , in order to enhance salt resistance and expand the application of rose. [ Methods ] The seedling of Chinese rose variety ‘ Yueyue Hong ’ was used as experimental material to con- duct indoor potting experiments. In addition , control ( CK ), 100 mol / L NaCl stress , root administration of MT , and root inoculation of AMF larvae of the genus Claroideoglomus etatunicum and their combina- tion were set to investigate the effects of each treatment on the growth of rose seedlings , chlorophyll fluo- rescence parameters , hormone metabolism , and antioxidant system. [ Results ] ( 1 ) Application of MT pro- moted AMF infestation of the roots of rose seedlings and increased the infection rate , bush growth rate , number of vesicles , and invasion points. ( 2 ) Under salt stress , the growth of rose seedlings was inhibited , and plant height , stem thickness , and biomass were decreased significantly. MT and AMF treatments in- creased the height , stem thickness , and biomass of rose seedlings , whereas AMF+MT treatment had no significant difference in plant height and stem thickness , aboveground dry weight and underground dry weight were increased by 24.1% and 37.0%. ( 3 ) Under salt stress , the chlorophyll content of rose seed- lings was decreased significantly while chlorophyll fluorescence parameters were decreased , and MT and AMF treatments could improve the chlorophyll content and chlorophyll fluorescence parameters. Under AMF+MT treatment , the total amount of chlorophyll and chlorophyll a / b was increased by 46.2% and 67.2% , respectively. PSⅡ maximum photochemical efficiency ( F v / F m ), potential activity ( F v / F o ), ac- tual photochemical efficiency ( Φ PSⅡ ), effective photochemical quantum efficiency ( F v ' / F m ' ), and photo- chemical quenching coefficient ( q P ) were increased by 4.9% , 51.0% , 175.0% , 168.7% , and 92.5% , re- spectively , whereas NPQ was decreased by 42.7%. ( 4 ) Under salt stress , zeatin ( ZT ), gibberellin ( GA ), auxin ( IAA ) content in leaves were decreased , whereas the abscisic acid ( ABA ) content was in- creased. MT and AMF contributed to the increase in ZT , GA , and IAA content and the decrease in ABA content. Under AMF+MT treatment , ZT , GA , and IAA content were increased by 146.9% , 116.9% , 35.7% , respectively , while ABA was decreased by 21.1%. ( 5 ) Under salt stress , the activity of SOD and CAT were increased , and the rate of superoxide anions ( O - · 2 ) production and H 2 O 2 accumulation was in- creased. MT and AMF treatments decreased O - · 2 production rate and H 2 O 2 content , while AMF+MT treatment activated SOD and CAT activity , and reduced the rate of O - · 2 production and H 2 O 2 accumula- tion. [ Conclusion ] Inoculation with AMF , addition of MT , or AMF+MT treatment could increase the chlorophyll content of rose seedlings under salt stress , protect the chlorophyll fluorescence system , main- tain the balance of endogenous plant hormones , activate the activity of antioxidant enzymes such as SOD and CAT , and reduce lipid peroxidation and H 2 O 2 accumulation , thereby reduce the damage caused by salt stress to rose seedlings , promote rose growth , and enhance the salt resistance of rose seedlings better with AMF+MT treatment.

In alkaline and neutral MEA CO2 electrolyzers, CO2 rapidly converts to (bi)carbonate, imposing a significant energy penalty arising from separating CO2 from the anode gas outlets. Here we report a CO2 electrolyzer uses a bipolar membrane (BPM) to convert (bi)carbonate back to CO2, preventing crossover; and that surpasses the single-pass utilization (SPU) limit (25% for multi-carbon products, C2+) suffered by previous neutral-media electrolyzers. We employ a stationary unbuffered catholyte layer between BPM and cathode to promote C2+ products while ensuring that (bi)carbonate is converted back, in situ, to CO2 near the cathode. We develop a model that enables the design of the catholyte layer, finding that limiting the diffusion path length of reverted CO2 to ~10 μm balances the CO2 diffusion flux with the regeneration rate. We report a single-pass CO2 utilization of 78%, which lowers the energy associated with downstream separation of CO2 by 10× compared with past systems.

Purpose Anxiety and pain commonly occur during nerve block, we aimed to investigate the sedation efficacy of different doses of remimazolam with sufentanil in young and elderly patients. Methods In this randomized trial, patients aged 18-85 years who underwent nerve block was enrolled. All patients received sufentanil 0.08 [mu]g/kg for analgesia. Young patients (age < 65 years) were randomized into the control group (Group C, 0.9% saline), medium-dose remimazolam (Group M, 0.06 mg/kg) and high-dose remimazolam group (Group H, 0.08 mg/kg). Elderly patients (age [greater than or equal to] 65 years) were randomized into the Group C, low-dose remimazolam group (Group L, 0.04 mg/kg) and Group M. Primary outcome was the success rate of procedure sedation. Respiratory depression and hypoxia were the interested safety outcomes. Results Ninety young and 114 elderly patients were enrolled, respectively. In comparison with Groups C and M, young patients in Group H had the highest success rate of procedure sedation (80.0 vs. 73.3 vs. 43.3%, P = 0.006). Elderly patients in Groups M and L had similar success rates of procedure sedation, which were significantly higher than that in Group C (78.9 vs. 78.9 vs. 50.0%, P = 0.007). In elderly patients, the incidence of respiratory depression and hypoxia tended to be higher in Group M than those in Groups L and C (both P < 0.001). Conclusion Remimazolam 0.08 mg/kg provided the best sedation efficacy in young patients while remimazolam 0.04 mg/kg with the trend of less respiratory adverse events was more optimal for elderly patients. Trial registration http://www.chictr.org.cn/showproj.aspx?proj=122016., Author(s): Xue Li [sup.1], Tegeleqi Bu [sup.1], Yu-Ting Li [sup.1], Ke-Qi Xie [sup.2], Zhen-Zhen Xu [sup.1], Xin-Quan Liang [sup.1], Dong-Liang Mu [sup.1] Author Affiliations: (1) grid.411472.5, 0000 0004 1764 1621, [...]