Foliar Application of Chitosan (CTS), γ-Aminobutyric Acid (GABA), or Sodium Chloride (NaCl) Mitigates Summer Bentgrass Decline in the Subtropical Zone.

Creeping bentgrass (Agrostis stolonifera) is an excellent cool-season turfgrass that is widely used in urban gardening, landscaping, and golf turf. Triennial field experiments from 2017 to 2019 were conducted to investigate effects of the foliar application of chitosan (CTS), γ-aminobutyric acid (GABA), or sodium chloride (NaCl) on mitigating summer bentgrass decline (SBD) and exploring the CTS, GABA, or NaCl regulatory mechanism of tolerance to summer heat stress associated with changes in chlorophyll (Chl) loss and photosynthetic capacity, osmotic adjustment (OA), oxidative damage, and cell membrane stability. The findings demonstrated that persistent ambient high temperatures above 30 °C during the summer months of 2017, 2018, and 2019 significantly reduced the turf quality (TQ), Chl content, photochemical efficiency of PSII (Fv/Fm and PIABS), leaf relative water content, and osmotic potential (OP) but significantly increased electrolyte leakage (EL) and the accumulations of free proline, water-soluble carbohydrate (WSC), hydrogen peroxide (H2O2), and malondialdehyde (MDA). The foliar application of CTS, GABA, or NaCl could significantly alleviate SBD, as reflected by improved TQ and delayed Chl loss during hot summer months. Heat-induced declines in Fv/Fm, PIABS, the net photosynthetic rate (Pn), the transpiration rate (Tr), and water use efficiency (WUE) could be significantly mitigated by the exogenous application of CTS, GABA, or NaCl. In addition, the foliar application of CTS, GABA, or NaCl also significantly improved the accumulations of free proline and WSC but reduced the EL, OP, and H2O2 content and the MDA content in leaves of creeping bentgrass in favor of water and redox homeostasis in summer. Based on the comprehensive evaluation of the subordinate function value analysis (SFVA), the CTS had the best effect on the mitigation of SBD, followed by GABA and NaCl in 2017, 2018, and 2019. The current study indicates that the foliar application of an appropriate dose of GABA, CTS, or NaCl provides a cost-effective strategy for mitigating SBD.

Genome-wide identification of Aux/IAA gene family in white clover (Trifolium repens L.) and functional verification of TrIAA18 under different abiotic stress.

BACKGROUND: White clover (Trifolium repens L.) is an excellent leguminous cool-season forage with a high protein content and strong nitrogen-fixing ability. Despite these advantages, its growth and development are markedly sensitive to environmental factors. Indole-3-acetic acid (IAA) is the major growth hormone in plants, regulating plant growth, development, and response to adversity. Nevertheless, the specific regulatory functions of Aux/IAA genes in response to abiotic stresses in white clover remain largely unexplored. RESULTS: In this study, we identified 47 Aux/IAA genes in the white clover genome, which were categorized into five groups based on phylogenetic analysis. The TrIAAs promoter region co-existed with different cis-regulatory elements involved in developmental and hormonal regulation, and stress responses, which may be closely related to their diverse regulatory roles. Collinearity analysis showed that the amplification of the TrIAA gene family was mainly carried out by segmental duplication. White clover Aux/IAA genes showed different expression patterns in different tissues and under different stress treatments. In addition, we performed a yeast two-hybrid analysis to investigate the interaction between white clover Aux/IAA and ARF proteins. Heterologous expression indicated that TrIAA18 could enhance stress tolerance in both yeast and transgenic Arabidopsis thaliana. CONCLUSION: These findings provide new scientific insights into the molecular mechanisms of growth hormone signaling in white clover and its functional characteristics in response to environmental stress.

Assessing cognitive workloads of assembly workers during multi-task switching.

Complex assembly tasks with multiple manual operations and steps often require rapid judgment and action under time pressure and cause most human-related errors. The task switching and action transitions are major sources of these errors. This study intends to implement an electroencephalography (EEG) approach to quantitatively evaluate the mental workload during task switching and transition. The time-frequency and spectrum analysis were utilized to compute and reflect the task demand between the intervals of individual tasks. This study developed an experiment to validate the proposed assessment approach and benchmark the results with the National Aeronautics and Space Administration task load index (NASA-TLX) subjective evaluation scale analysis. The results show that the average value of the power spectral densities (PSDs) of the gamma band signal of the AF4 channel and the beta band signal of Channel F3 show distinctive signal patterns among task stages and intervals. During the interval between the idling stage and the part selection stage, the peak of the PSD envelope increased from 18 to 27 Hz, suggesting advanced cognition increases the mental workload of the interval between different tasks. Therefore, the task switching period cannot be regarded as rest and need to be optimized with better task organization.

Optimization of Protocols for the Induction of Callus and Plant Regeneration in White Clover (Trifolium repens L.).

White clover is a widely grown temperate legume forage with high nutritional value. Research on the functional genomics of white clover requires a stable and efficient transformation system. In this study, we successfully induced calluses from the cotyledons and leaves of 10 different white clover varieties. The results showed that the callus formation rate in the cotyledons did not vary significantly among the varieties, but the highest callus formation rate was observed in 'Koala' leaves. Subsequently, different concentrations of antioxidants and hormones were tested on the browning rate and differentiation ability of the calluses, respectively. The results showed that the browning rate was the lowest on MS supplemented with 20 mg L-1 AgNO3 and 25 mg L-1 VC, respectively, and the differentiation rate was highest on MS supplemented with 1 mg L-1 6-BA, 1 mg L-1 KT and 0.5 mg L-1 NAA. In addition, the transformation system for Agrobacterium tumefaciens-mediated transformation of 4-day-old leaves was optimized to some extent and obtained a positive callus rate of 8.9% using green fluorescent protein (GFP) as a marker gene. According to our data, by following this optimized protocol, the transformation efficiency could reach 2.38%. The results of this study will provide the foundation for regenerating multiple transgenic white clover from a single genetic background.

EEG-Based Driver Fatigue Monitoring within a Human-Ship-Environment System: Implications for Ship Braking Safety.

To address the uncontrollable risks associated with the overreliance on ship operators' driving in current ship safety braking methods, this study aims to reduce the impact of operator fatigue on navigation safety. Firstly, this study established a human-ship-environment monitoring system with functional and technical architecture, emphasizing the investigation of a ship braking model that integrates brain fatigue monitoring using electroencephalography (EEG) to reduce braking safety risks during navigation. Subsequently, the Stroop task experiment was employed to induce fatigue responses in drivers. By utilizing principal component analysis (PCA) to reduce dimensionality across multiple channels of the data acquisition device, this study extracted centroid frequency (CF) and power spectral entropy (PSE) features from channels 7 and 10. Additionally, a correlation analysis was conducted between these features and the Fatigue Severity Scale (FSS), a five-point scale for assessing fatigue severity in the subjects. This study established a model for scoring driver fatigue levels by selecting the three features with the highest correlation and utilizing ridge regression. The human-ship-environment monitoring system and fatigue prediction model proposed in this study, combined with the ship braking model, achieve a safer and more controllable ship braking process. By real-time monitoring and prediction of driver fatigue, appropriate measures can be taken in a timely manner to ensure navigation safety and driver health.

Effects of tri-n-butyl phosphate (TnBP) on neurobehavior of Caenorhabditis elegans.

As an emerging flame retardant, organic phosphate flame retardants have been extensively used worldwide. The aim of this study is to determine the effects of TnBP on neurobehavior of Caenorhabditis elegans (C. elegans) and its mechanisms. L1 larvae of wild-type nematodes (N2) were exposed to TnBP of 0, 0.1, 1, 10, and 20 mg/L for 72 hours. Then, we observed that the body length and body width were inhibited, the head swings were increased, the pump contractions and chemical trend index were reduced, the production of reactive oxygen species (ROS) was increased, and the expression of mitochondrial oxidative stress related genes (mev-1 and gas-1) and P38 MAPK signal pathway-related genes (pmk-1, sek-1, and nsy-1) was altered. After reporter gene strains BZ555, DA1240, and EG1285 were exposed to TnBP of 0, 0.1, 1, 10, and 20 mg/L for 72 hours, the synthesis of dopamine, glutamate, and Gamma-Amino Butyric Acid (GABA) was increased. In addition, the pmk-1 mutants (KU25) led to the sensitivity of C. elegans to TnBP in terms of head swings. The results showed that TnBP had harmful effects on the neurobehavior of C. elegans, oxidative stress might be one of the mechanisms of its neurotoxicity, and P38 MAPK signal pathway might play an important regulatory role in this process. The results revealed the potential adverse effects of TnBP on the neurobehavior of C. elegans.

Assessing Passengers' Motion Sickness Levels Based on Cerebral Blood Oxygen Signals and Simulation of Actual Ride Sensation.

(1) Background: After motion sickness occurs in the ride process, this can easily cause passengers to have a poor mental state, cold sweats, nausea, and even vomiting symptoms. This study proposes to establish an association model between motion sickness level (MSL) and cerebral blood oxygen signals during a ride. (2) Methods: A riding simulation platform and the functional near-infrared spectroscopy (fNIRS) technology are utilized to monitor the cerebral blood oxygen signals of subjects in a riding simulation experiment. The subjects' scores on the Fast Motion sickness Scale (FMS) are determined every minute during the experiment as the dependent variable to manifest the change in MSL. The Bayesian ridge regression (BRR) algorithm is applied to construct an assessment model of MSL during riding. The score of the Graybiel scale is adopted to preliminarily verify the effectiveness of the MSL evaluation model. Finally, a real vehicle test is developed, and two driving modes are selected in random road conditions to carry out a control test. (3) Results: The predicted MSL in the comfortable mode is significantly less than the MSL value in the normal mode, which is in line with expectations. (4) Conclusions: Changes in cerebral blood oxygen signals have a huge correlation with MSL. The MSL evaluation model proposed in this study has a guiding significance for the early warning and prevention of motion sickness.

Study of Motion Sickness Model Based on fNIRS Multiband Features during Car Rides.

Motion sickness is a common physiological discomfort phenomenon during car rides. In this paper, the functional near-infrared spectroscopy (fNIRS) technique was used in real-world vehicle testing. The fNIRS technique was utilized to model the relationship between changes in blood oxygenation levels in the prefrontal cortex of passengers and motion sickness symptoms under different motion conditions. To enhance the accuracy of motion sickness classification, the study utilized principal component analysis (PCA) to extract the most significant features from the test data. Wavelet decomposition was used to extract the power spectrum entropy (PSE) features of five frequency bands highly related to motion sickness. The correlation between motion sickness and cerebral blood oxygen levels was modeled by a 6-point scale calibration for the subjective evaluation of the degree of passenger motion sickness. A support vector machine (SVM) was used to build a motion sickness classification model, achieving an accuracy of 87.3% with the 78 sets of data. However, individual analysis of the 13 subjects showed a varying range of accuracy from 50% to 100%, suggesting the presence of individual differences in the relationship between cerebral blood oxygen levels and motion sickness symptoms. Thus, the results demonstrated that the magnitude of motion sickness during the ride was closely related to the change in the PSE of the five frequency bands of cerebral prefrontal blood oxygen, but further studies are needed to investigate individual variability.

Neurotoxicity of Tris (1,3-dichloroisopropyl) phosphate in Caenorhabditis elegans.

As a new type of flame retardant, Organic Phosphate Flame Retardant has been widely used worldwide. The purpose of our research is to determine the neurotoxicity of Tris (1,3-dichloroisopropyl) phosphate (TDCPP) to Caenorhabditis elegans and its mechanism. L1 larvae wild-type C. elegans were exposed to different concentrations of TDCPP, and the effects on motor behavior (head thrashes, body bends, pumping times, chemotaxis index), ROS levels, and p38MAPK signaling pathway-related gene expression levels were measured. Three transgenic nematode strains, BZ555, DA1240, and EG1285, were also used to study the effects of TDCPP on nematode dopamine neurons, glutamate neurons, and GABA neurons. The results showed that TDCPP can inhibit the head thrashes and body bends of the nematode, reduce dopamine production, increase the level of ROS in the body, and affect the expression of genes related to the p38MAPK signaling pathway. We next employed ROS production and motor behavior as toxicity assessment endpoints to determine the involvement of p38 MAPK signaling in the regulation of response to TDCPP. The results showed that the nematodes with low expression of pmk-1 were less sensitive to the TDCPP. It was suggested that TDCPP had neurotoxicity and regulated neurotoxicity to C. elegans by activating the p38-MAPK signaling pathway. The research in this article provides important information for revealing the environmental health risks of organophosphorus flame retardants and their toxic mechanism of action.

Study on the reproductive toxicity and mechanism of tri-n-butyl phosphate (TnBP) in Caenorhabditis elegans.

Tri-n-butyl phosphate (TnBP), a typical alkyl organophosphate ester is widely used as an emerging flame retardant for polybrominated diphenyl ethers alternatives, but the potential toxicity and mechanism are unclear. In this study, the reproductive toxicity of TnBP and its related mechanisms were explored using the Caenorhabditis elegans (C. elegans) model. After TnBP (100-1000 µg/L) exposure, brood size and the number of fertilized eggs in the uterus in C. elegans were significantly reduced, the relative area of gonad arm and the number of total germline cells in C. elegans were significantly reduced, germ cell apoptosis and germ cell DNA damage in C. elegans were significantly increased, the level of ROS in C. elegans was significantly increased. Furthermore, TnBP exposure caused abnormal gene expressions of cell apoptosis (ced-9, ced-4 and ced-3), DNA damage (hus-1, clk-2, cep-1 and egl-1) and oxidative stress (mev-1 and gas-1). TnBP exposure can lead to reproductive ability decreased and gonad development impaired in C. elegans, the mechanism of TnBP reduced reproductive ability may be related to germ cell apoptosis, germ cell DNA damage and oxidative stress. Environmental exposure to TnBP may have potential reproductive toxicity.

Bacillus coagulans 13002 and fructo-oligosaccharides improve the immunity of mice with immunosuppression induced by cyclophosphamide through modulating intestinal-derived and fecal microbiota.

This study aims to evaluate the effects of probiotic Bacillus coagulans 13,002 (BCS) and prebiotic fructo-oligosaccharides (FOS) on mice treated with the alkylating agent cyclophosphamide (CTX). We found that both BCS and FOS, especially BCS, significantly alleviated CTX-induced injury by modulating intestinal-derived and fecal microbiota. BCS and BCS + FOS increased serum immunoglobulin levels, which were reduced by CTX. In addition, BCS and BCS + FOS upregulated IFN-γ and IL-4, which protect mucosal barriers and the balance of Th1/Th2. BCS promoted the growth of some beneficial bacteria, such as Bacteroides, Coprococcus, Enterococcus, Oscillospira, and Ruminococcus in mouse gut. In addition, BCS + FOS inhibited the growth of several harmful bacteria, including Acinetobacter, Arthrobacter, Brachybacterium, Corynebacterium, Jeotgalicoccus, Sporosarcina, and Staphylococcus. Furthermore, BCS potentially improved the growth of Anaerotruncus bacteria, which can promote the production of butyrate acids. In summary, according our results suggest that BCS and FOS improved the immunity of mice with immunosuppression induced by CTX through modulating intestinal-derived and fecal microbiota.

Streptococcus thermophiles DMST-H2 Promotes Recovery in Mice with Antibiotic-Associated Diarrhea.

Antibiotic-associated diarrhea (AAD) is the most common side effect of antibiotics and is routinely treated with probiotics in clinical. Streptococcus thermophiles, extensively utilized for producing dairy foods, has recently been regarded as a new promising probiotic candidate. In this study, the efficacy of Streptococcus thermophiles DMST-H2 (DMST-H2) for AAD treatment in mice was investigated. DMST-H2 was isolated from Chinese traditional yogurt, proved to be non-toxic, and presented tolerance against simulated gastrointestinal conditions in vitro. Additionally, genomic analysis revealed that it possessed genes related to acid tolerance, bile salt tolerance, adhesion, oxidative stress and bacteriocin production. The animal experiment results showed that both DMST-H2 treatment and natural recovery could reduce fecal water content. Compared with spontaneous recovery, DMST-H2 accelerated the recovery of the enlarged caecum and intestinal barrier injury from AAD, and further decreased endotoxin (ET), D-lactate (D-LA) and diamine oxidase (DAO) content in serum. Moreover, pro-inflammatory cytokines (TNF-α) were reduced, while interferon-γ (IFN-γ) and anti-inflammatory cytokines (IL-10) increased after treating with DMST-H2. Furthermore, DMST-H2 better restored the structure of intestinal flora. At the phylum level, Firmicutes increased and Proteobacteria decreased. These findings indicate that DMST-H2 could promote recovery in mice with antibiotic-associated diarrhea.