The plant growth promoting rhizobacteria (PGPR) and plant growth regulators (PGRs) can be applied to improve the growth and productivity of plants, with potential to be used for genetic improvement ...of drought tolerance. However, for genetic improvement to be achieved, a solid understanding of the physiological and biochemical changes in plants induced by PGPR and PGR is required. The present study was carried out to investigate the role of PGPR and PGRs on the physiology and biochemical changes in chickpea grown under drought stress conditions and their association with drought tolerance. The PGPR, isolated from the rhizosphere of chickpea, were characterized on the basis of colony morphology and biochemical characters. They were also screened for the production of indole-3-acetic acid (IAA), hydrogen cyanide (HCN), ammonia (NH
), and exopolysaccharides (EPS) production. The isolated PGPR strains, named P1, P2, and P3, were identified by 16S-rRNA gene sequencing as Bacillus subtilis, Bacillus thuringiensis, and Bacillus megaterium, respectively. The seeds of two chickpea varieties, Punjab Noor-2009 (drought sensitive) and 93127 (drought tolerant) were soaked for 2-3 h prior to sowing in 24 h old cultures of isolates. The salicylic acid (SA) and putrescine (Put) were sprayed (150 mg/L) on 25 day old chickpea seedlings. The results showed that chickpea plants treated with a consortium of PGPR and PGRs significantly enhanced the chlorophyll, protein, and sugar contents compared to irrigated and drought conditions. Leaf proline content, lipid peroxidation, and activities of antioxidant enzymes (CAT, APOX, POD, and SOD) all increased in response to drought stress but decreased due to the PGPR and PGRs treatment. An ultrahigh performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) analysis was carried out for metabolic profiling of chickpea leaves planted under controlled (well-irrigated), drought, and consortium (drought plus PGPR and PGRs) conditions. Proline, L-arginine, L-histidine, L-isoleucine, and tryptophan were accumulated in the leaves of chickpea exposed to drought stress. Consortium of PGPR and PGRs induced significant accumulation of riboflavin, L-asparagine, aspartate, glycerol, nicotinamide, and 3-hydroxy-3-methyglutarate in the leaves of chickpea. The drought sensitive chickpea variety showed significant accumulation of nicotinamide and 4-hydroxy-methylglycine in PGPR and PGR treated plants at both time points (44 and 60 days) as compared to non-inoculated drought plants. Additionally, arginine accumulation was also enhanced in the leaves of the sensitive variety under drought conditions. Metabolic changes as a result of drought and consortium conditions highlighted pools of metabolites that affect the metabolic and physiological adjustments in chickpea that reduce drought impacts.
Understanding the contrasting biochemical changes in different plant parts in response to drought can help to formulate smart strategies to develop drought tolerant genotypes. The current study used ...metabolomics and physiological approaches to understand the differential biochemical changes coupled with physiological adjustments in leaves and roots to cope with drought stress in two wheat genotypes, LA754 (drought tolerant) and AGS2038 (drought sensitive). The gas chromatography-mass spectrometry (GC-MS) analysis and physiological trait estimation were performed in the roots and leaves after drought imposition. Drought induced reduction was observed in all physiological and yield related traits. In LA754, higher numbers of metabolites were altered in leaves (45) compared to roots (20) which indicates that plants allocated more resources to leaves in tolerant genotype. In addition, the metabolic components of the root were less affected by the stress which supports the idea that the roots are more drought tolerant than the leaf or shoot. In AGS2038, thirty and twenty eight metabolites were altered in the leaves and roots, respectively. This indicates that the sensitive genotype compromised resource allocation to leaves, rather allocated more towards roots. Tryptophan, valine, citric acid, fumaric acid, and malic acid showed higher accumulation in leaf in LA754, but decreased in the root, while glyceric acid was highly accumulated in the root, but not in the leaf. The results demonstrated that the roots and shoots have a different metabolic composition, and shoot metabolome is more variable than the root metabolome. Though the present study demonstrated that the metabolic response of shoots to drought contrasts with that of roots, some growth metabolites (protein, sugar, etc) showed a mirror increase in both parts. Protein synthesis and energy cycle was active in both organs, and the organs were metabolically activated to enhance water uptake and maintain growth to mitigate the effect of drought.
In clinical conditions, polysomnography (PSG) is regarded as the "golden standard" for detecting sleep disease and offering a reference of objective sleep quality. For healthy adults, scores from ...sleep questionnaires are more reliable than other methods in obtaining knowledge of subjective sleep quality. In practice, the need to simplify PSG to obtain subjective sleep quality by recording a few channels of physiological signals such as single-lead electrocardiogram (ECG) or photoplethysmography (PPG) signal is still very urgent. This study provided a two-step method to differentiate sleep quality into "good sleep" and "poor sleep" based on the single-lead wearable cardiac cycle data, with the comparison of the subjective sleep questionnaire score. First, heart rate variability (HRV) features and ECG-derived respiration features were extracted to construct a sleep staging model (wakefulness (W), rapid eye movement (REM), light sleep (N1&N2) and deep sleep (N3)) using the multi-classifier fusion method. Then, features extracted from the sleep staging results were used to construct a sleep quality evaluation model, i.e., classifying the sleep quality as good and poor. The accuracy of the sleep staging model, tested on the international public database, was 0.661 and 0.659 in Cardiology Challenge 2018 training database and Sleep Heart Health Study Visit 1 database, respectively. The accuracy of the sleep quality evaluation model was 0.786 for our recording subjects, with an average F
-score of 0.771. The proposed sleep staging model and sleep quality evaluation model only requires one channel of wearable cardiac cycle signal. It is very easy to transplant to portable devices, which facilitates daily sleep health monitoring.
Metabolic disease is a significant risk factor for severe COVID-19 infection, but the contributing pathways are not yet fully elucidated. Using data from two randomized controlled trials across 13 ...U.S. academic centers, our goal was to characterize metabolic features that predict severe COVID-19 and define a novel baseline metabolomic signature. Individuals (n = 133) were dichotomized as having mild or moderate/severe COVID-19 disease based on the WHO ordinal scale. Blood samples were analyzed using the Biocrates platform, providing 630 targeted metabolites for analysis. Resampling techniques and machine learning models were used to determine metabolomic features associated with severe disease. Ingenuity Pathway Analysis (IPA) was used for functional enrichment analysis. To aid in clinical decision making, we created baseline metabolomics signatures of low-correlated molecules. Multivariable logistic regression models were fit to associate these signatures with severe disease on training data. A three-metabolite signature, lysophosphatidylcholine a C17:0, dihydroceramide (d18:0/24:1), and triacylglyceride (20:4_36:4), resulted in the best discrimination performance with an average test AUROC of 0.978 and F1 score of 0.942. Pathways related to amino acids were significantly enriched from the IPA analyses, and the mitogen-activated protein kinase kinase 5 (MAP2K5) was differentially activated between groups. In conclusion, metabolites related to lipid metabolism efficiently discriminated between mild vs. moderate/severe disease. SDMA and GABA demonstrated the potential to discriminate between these two groups as well. The mitogen-activated protein kinase kinase 5 (MAP2K5) regulator is differentially activated between groups, suggesting further investigation as a potential therapeutic pathway.
The understanding of the structure–activity relationship can help us design desired functional materials. SiO2 shell is widely used as a physicochemical inert layer to protect materials from ...corrosion or oxidization. But, in electromagnetic (EM) absorption studies, silica shell, supposed to be EM transparent, has been found to significantly influence the EM absorption performance. Here, we studied the microstructure, EM parameters, and electronic structure of silica shell coated SiC/Co (SiC/Co@SiO2) nanowires to figure out the nature of silica shell influencing on their EM absorption. X-ray absorption near-edge structures on Co L3,2-edge and O K-edge analysis confirm that silica links with Co by Si–O–Co bonds. Electron transfer takes place between silica and Co, which leads to formation of gradient ε field within silica and more incident EM wave entering into the absorbers. Generating significant interfacial polarization, the silica shell improves the EM absorption performance. The present research offers a novel insight on the functional role of silica shell.
In this research, we examined the impact of icons' depth on user attention and search efficiency during icon recognition. First, 61 participants were asked to view an image composed of flat (2D) and ...neumorphic (3D) icons arranged in a circle, with their eye movements monitored by an eye tracker. Each participant was asked to watch the pictures carefully then complete four search tasks under the following four conditions (with suitable prompts) while viewing them: selecting a target 2D icon from among 2D icons, selecting a target 3D icon from among 3D icons, selecting a target 2D icon from among mixed 2D and 3D icons, and selecting a target 3D icon from among mixed 2D and 3D icons. The results indicated that 3D icons performed better in terms of attention distribution and attention attraction than 2D icons. There were no significant differences in terms of search time or accuracy between selecting a target 2D icon from among 2D icons and selecting a target 3D icon from among 3D icons, selecting a target 2D icon from among mixed 2D and 3D icons, and selecting a target 3D icon from among mixed 2D and 3D icons. The findings have practical significance for icon design and can provide guidance for designers, prompting them to either use 2D or 3D icons to achieve intentional visual and cognitive effects.
•The depth information of icons affects users' visual attention significantly.•Neumorphic 3D icons are better in terms of attracting attention than 2D icons.•There was no significant difference in terms of search efficiency between 2D and neumorphic 3D icons.
The Cosmos 1408 man-made breakup event generated a large number of fragments. These fragments pose a threat to the operating spacecrafts in the Low Earth Orbit (LEO). The lifetimes of cataloged ...Cosmos 1408 fragments are shorter than those of fragments simulated by NASA's breakup model. Therefore, the particle swarm optimization (PSO) was used to modify the parameters in the breakup model, and the modified debris cloud highly matches the SSN cataloged fragments. The Cosmos debris cloud was simulated by the optimized breakup model, and the impact of this event on the space debris environment, the International Space Station (ISS) and the Chinese Space Station (CSS) was analyzed by applying Space Debris Environment Engineering Model 2019 (SDEEM 2019) and Survivability of Spacecraft in Space Debris Environment (S3DE). The results show that most (90%) dangerous debris was estimated to reenter within one year due to atmospheric drag. The sensitivity analysis for the ISS and the CSS shows that the sensitivity of the threatening debris of the ISS and the CSS increases about 40% and 50% over a future decade compared to that without this event, respectively.
•Debris reentry rate can be fitted by modifying the area-to-mass distribution.•Particle swarm optimization algorithm is used for optimizing the breakup model.•Impact of the Cosmos 1408 fragments on space debris environment decreases rapidly.•Probability of impact on two space stations by dangerous debris increases in a decade.
This study explored the emotional influence of pupillary change (PC) of robots with different human-likeness levels on people. Images of the eye areas of five agents, including one human and four ...existing typical humanoid robots with varying human-likeness levels, were edited into five 27-s videos. In the experimental group, we showed five videos with PC applied to the eyes of agents to 31 participants, and in the control group, five videos without PC were shown to another 31 participants. Afterward, the participants were asked to rate their feelings about the videos. The results showed that PC did not change people’s emotions towards agents independently. However, PC applied to the eyes of a robot representing an agent of no threat who may evoke empathy subconsciously enhanced people’s positive emotions, while PC applied to human images increased people’s negative emotions and reduced the feeling of familiarity.
AbstractIn order to obtain the lunar lander soft landing performance impact caused by the body gravity centerline shift, a seven-degree-of-freedom dynamic model is established based on the inertia ...force, and a dynamics and kinematics equation is deduced. The dynamic model was verified by the lunar lander scale model and soft landing impact experimental platform. Soft landing performance effects caused by the lander body gravity centerline shifts are analyzed according to the displacement of the body, the body overload, primary/secondary pillar load, and buffer processes. The research results show that the gravity centerline shift has a significant influence on the lunar lander soft landing performance; when the lunar lander lands on the lunar slope—in a downward direction along the slope—the appropriate shift of the position of the gravity centerline can effectively improve the soft landing performance and stability.
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