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Abstract This study aimed to evaluate the influence of CO2 and temperature on glyphosate-resistant and susceptible biotypes of Amaranthus palmeri (Palmer amaranth) in terms of morphological development. Height (cm), stem diameter (cm), leaf area (cm2), number of leaves, leaf, stem, and root dry matter, plant volume (m3), as well as shoot-to-root allometry were evaluated. The Palmer amaranth biotypes were grown under four different scenarios: 1—low temperature (23/33 °C) and CO2 (410 ± 25 ppm); 2—low temperature (23/33 °C) and high CO2 (750 ± 25 ppm); 3—high temperature (26/36 °C) and low CO2 (410 ± 25 ppm); and 4—high temperature (26/36 °C) and CO2 (750 ± 25 ppm). Between CO2 and temperature, the majority of differences observed were driven by CO2 levels. Palmer amaranth grown under 750 ppm of CO2 was 15.5% taller, displayed 10% more leaf area (cm2), 18% more stem dry matter, and had a 28.4% increase in volume (m3) compared to 410 ppm of CO2. GA2017 and GA2020 were 18% and 15.5% shorter, respectively. The number of leaves was 27% greater for GA2005. Plant volume decreased in GA2017 (35.6%) and GA2020 (23.8%). The shoot-to-root ratio was isomeric, except at 14 and 21 DAT, where an allometric growth towards shoot development was significant. Palmer amaranth biotypes responded differently to elevated CO2, and the impacts of temperature need further investigation on weed physiology. Thus, environmental and genetic background may affect the response of glyphosate-resistant and susceptible populations to climate change scenarios.

Temperature affects the growth and development of tobacco. With the frequent occurrence of extreme high and low temperature disasters, temperature stress has become one of the important factors restricting the normal growth and physiological functions of flue-cured tobacco. Low temperature stress and high temperature stress are currently the most common disasters in the seedling and maturity stages of flue-cured tobacco, which have a serious impact on the quality and yield of flue-cured tobacco. This article reviews the effects of temperature stress on physiological mechanisms such as growth and development, photosynthetic function, carbon and nitrogen metabolism, and antioxidant system of flue-cured tobacco. It introduced the research progress of related plant proteins and molecular mechanisms in temperature stress, and systematically summarizes the current stress resistance control measures for field temperature stress, including field management and spraying exogenous substances. At present, most agronomic interventions for temperature stress management may not be complete. It is necessary to understand the genetic, biochemical and physiological processes of different varieties in order to identify and select traits, enhance their high-temperature resistance mechanism, and cultivate high-temperature resistant flue-cured tobacco varieties. Looking forward to future research on temperature stress in flue-cured tobacco, including exploring local germplasm resources, cultivating heat-resistant varieties, utilizing methods such as multi omics or cross omics to deeply explore the response mechanism of temperature stress in flue-cured tobacco, developing predictive research on temperature stress in flue-cured tobacco, and developing targeted management measures for stress resistance cultivation, in order to provide scientific support for the prevention of climate disasters and the enhancement of agricultural disaster reduction efficiency for flue-cured tobacco.

BackgroundTotal knee arthroplasty (TKA) is currently the main treatment for end-stage knee disease. The number of cases of TKA in China increased from 53,880 in 2011 to 374,833 in 2019, representing a 5.9-fold increase. Moderate to severe pain often occurs after TKA, which seriously affects postoperative rehabilitation, patient satisfaction, and overall outcome. Multimodal analgesia is considered the ideal solution. Adequate postoperative analgesia can not only reduce pain, opioid consumption, and, consequently, opioid-related adverse events, but can also reduce the length of hospital stay and costs and improve rehabilitation and patient satisfaction. ObjectiveEffective multimodal pain management in the early postoperative period is essential for anesthesiologists. Additional studies have demonstrated that a low-dose intravenous infusion of ketamine can be administered as an adjuvant drug to alleviate acute postoperative pain. Therefore, we aim to appraise the efficacy and safety of intraoperative intravenous injection of S(+)-ketamine to relieve acute pain after TKA in older patients. MethodsThis is a protocol for a randomized, placebo-controlled trial. A total of 144 participants aged 65 years and older undergoing TKA will be randomly allocated into the S(+)-ketamine and placebo groups in a 1:1 ratio. S(+)-ketamine or the placebo will be intravenously administered at 0.3 mg/kg/h during the operation by anesthesiologists. Blinded evaluation by trained investigators will be completed at 2 hours, 24 hours, and 48 hours after surgery. The primary outcome measure will be the numeric rating scale score at rest and movement at 24 hours after surgery. The secondary outcomes will include the numeric rating scale scores at rest and movement at 2 hours and 48 hours after surgery, the number of patients who require additional analgesics during the first 48 hours after operation, the total consumption of opioids or nonsteroid anti-inflammatory drugs during the first 48 hours after operation, and adverse events at 2, 24, and 48 hours after operation. ResultsThe protocol was registered at Clinical Trials.gov on February 26, 2022. It was performed in accordance with the approved guidelines and regulations of the participating institutions. Recruitment began in April 2022. Data collection is expected to conclude in September 2024. Study completion is expected in December 2024. ConclusionsA randomized, controlled, clinical study was designed to observe the analgesic effect of intraoperative intravenous administration of a lower dose of S(+)-ketamine (0.3 mg/kg/h) in older patients after TKA surgery. The protocol will appraise the efficacy and safety of intraoperative intravenous injection of S(+)-ketamine to relieve acute pain after TKA in older patients who may benefit from the administration of S(+)-ketamine. Trial RegistrationClinicalTrials.gov NCT05289050; https://clinicaltrials.gov/ct2/show/NCT05289050 International Registered Report Identifier (IRRID)DERR1-10.2196/53063

The Oenothein B (OEB) rich in eucalyptus is a kind of extremely development of prospects of antioxidant activity, but low oral bioavailability limits its application. The novel polyelectrolyte nanoparticle was designed for OEB delivery through the self-assembly of casein phosphopeptides (CPP) and natural active polysaccharides-chitosan (CS). The OEB nanoparticle with small particle size and high embedding rate were constructed to solve the problem of low oral bioavailability of OEB, and its stability as well as in vivo absorption were investigated. The storage stability analysis, digital inverted fluorescence microscopy and emission field scanning electron microscopy showed that the particle size and total amount of OEB nanoparticles did not vary significantly after 96 h of continuous storage at room temperature, and the particle size distribution was uniform, and the particles kept their integrity pH 1.2. The maximum release rate of OEB nanoparticles was only 0.72% in artificial gastric fluid and 21.77% in artificial intestinal fluid. It greatly reduces the risk of its decomposition and plays a better protective role. The results of in vivo absorption showed that OEB nanoparticle gavage mice did not detect OEB in blood and its metabolites except for OEB in gastric juice, indicating that OEB changes in vivo after release. Therefore, although OEB nanoparticles can effectively protect their decomposition in gastrointestinal fluid, it is best to achieve sustained release at the target location in order to improve the absorption and utilization effect.

The forced responses of bladed disks are highly sensitive to inevitable random mistuning. Considerable computational efforts are required for the sampling process to assess the statistical vibration properties of mistuned bladed disks. Therefore, efficient surrogate models are preferred to accelerate the process for probabilistic analysis. In this paper, four surrogate models are utilized to construct the relation between random mistuning and forced response amplitudes, which are polynomial chaos expansion (PCE), response surface method (RSM), artificial neural networks (ANN) and Kriging interpolation, respectively. A bladed disk with 2-degrees-of-freedom (2-DOF) each sector is used to validate the effectiveness of the surrogate models. The effects of number of training samples on the surrogate model accuracy are discussed. The responses results of one blade (single output) and maximum response of all blades (multi-output) indicate that PCE and Kriging interpolation could yield accurate and stable predictions of the statistical characteristics of the forced responses. PCE is recommended for the mistuned response predictions due to its accuracy and efficiency. [ABSTRACT FROM AUTHOR]