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Study of aerodynamic characteristics of variable cross-section box girders under three-dimensional fluctuating wind field
Effects of date palm and green tea polyphenol extracts on the thermal stability and mechanical properties of poly lactic acid
Identification of multiple ocular diseases using a hybrid quantum convolutional neural network with fundus images
Exogenous ascorbic acid enhances drought tolerance in Hypericum perforatum L. by modulating antioxidant defense and osmotic adjustment
Abstract Drought stress poses a significant threat to the cultivation of Hypericum perforatum L. (St. John’s wort), a valuable medicinal plant. While ascorbic acid (AsA) is a known mitigator of abiotic stress, its protective role and underlying mechanisms in H. perforatum remain unexplored. This study elucidates the biochemical and physiological basis of exogenous AsA-induced drought tolerance in H. perforatum subjected to full irrigation (100% FI), moderate (75% FI), and severe (50% FI) deficit irrigation. Severe drought significantly inhibited growth, reducing biomass, chlorophyll content, relative water content, and leaf area. Foliar application of AsA, particularly at 400 mg L − 1 , markedly ameliorated these inhibitory effects. The AsA-mediated mitigation was mechanistically linked to a robust enhancement of the plant’s antioxidant defense system, evidenced by significantly increased activities of ascorbate peroxidase, catalase, and superoxide dismutase, alongside elevated levels of endogenous AsA, total phenolics, and osmolytes (proline and soluble carbohydrates). Consequently, AsA-pretreated plants exhibited substantially reduced oxidative damage, with lower levels of malondialdehyde and electrolyte leakage under severe stress. Our findings demonstrate that exogenous AsA fortifies drought tolerance in H. perforatum primarily by orchestrating a synergistic enhancement of osmotic adjustment and reactive oxygen species scavenging capacity. This effective and practical strategy highlights the potential of AsA application to sustain the production of this economically important species in water-limited environments.
Design and implementation of a 6-DoF robot arm control with object detection based on machine learning using mini microcontroller
Cluster analysis reveals increasing plume-like magmatism during progressive rifting in Afar (Ethiopia)
Metabolomic-driven prediction of the mutational status of healthy individuals with a family history of hereditary breast and ovarian cancer syndrome: the HRRmet study
Upstream migration of the invasive blue crab in the Po River, Italy, highlights the vulnerability of freshwater ecosystems
River extraction from high-resolution remote sensing images based on non-uniform sampling and semi-supervised learning
Mechanism of Saikosaponin D in regulating ferroptosis in patient-derived lung adenocarcinoma organoids via upregulation of ATF3/CHOP/CHAC1 signaling
Influence of coaching experience on in-game adaptability and decision-making among basketball coaches
Ononin suppresses tumor-induced platelet activation and invasion and enhances cell-cycle arrest and apoptosis in triple-negative breast cancer cells
Enhancing SOC accuracy in electric vehicle batteries via trapezoidal integration and capacity degradation compensation
Pyridinium- and bromine-substituted distyryl-BODIPY dyes for mitochondria-targeted photodynamic therapy
Abstract A series of 1-methylpyridinium-substituted brominated distyryl-BODIPY dyes, PyB X I ( X = H, M, or Br), was synthesized to achieve cooperative singlet oxygen ( 1 O 2 ) production through qualitatively different dual intersystem crossing (ISC) pathways: spin–orbit charge-transfer ISC (SOCT-ISC) and heavy-atom-induced ISC. Upon photoexcitation of the PyB X I dyes, charge-transfer states were preferentially formed through photoinduced electron transfer from the distyryl-BODIPY core to the 1-methylpyridinium moiety, however, followed by nonradiative charge recombination rather than the desired SOCT-ISC. This resulted in negligible fluorescence and 1 O 2 quantum yields in the non-brominated dye PyBHI. The introduction of bromine atoms improved 1 O 2 quantum yield from 0.0034 for the mono-brominated dye PyBMI to 0.0061 for the di-brominated dye PyBBrI, attributable to the heavy atom effect. Nonetheless, the 1 O 2 production efficiency of these dyes remained limited, as photoinduced electron transfer was considered to occur nearly two orders of magnitude faster than singlet-to-triplet ISC. In vitro assays using MCF-7 and HeLa cells demonstrated that PyBBrI induced significant cell death, with IC 50 values of ca. 95 and 220 nM, respectively, confirming its potential for use in cancer therapy.
Determinants of poor glycemic control in children with type 1 diabetes mellitus in Northwest Ethiopia
Near-source wastewater surveillance as a non-invasive tool for disease detection in prisons
Abstract Near-source wastewater-based epidemiology (WBE) offers a non-intrusive alternative to clinical testing of whole prison populations. Prisons sit at the centre of high transmission risk but experience limited health-care access and barriers to testing individual prisoners. However, the use of WBE for health protection in prison settings has been limited. To assess its merit during the COVID-19 pandemic, SARS-CoV-2 RNA concentrations were quantified in 680 composite wastewater samples collected from 14 prisons across England and Wales between January and June 2021. Viral RNA was detected in 48% of samples, and wastewater viral loads were found to closely mirror clinical case numbers Lead–lag analysis with adjacent municipal wastewater samples indicated a bidirectional flow between the prisons and their local community: seven prisons exhibited wastewater peaks ahead of their communities, while six lagged, highlighting heterogeneous epidemiological coupling. Marked differences between prisons were apparent in both physicochemical wastewater traits and clinical testing uptake, indicating each institution constitutes a distinct surveillance unit. Collectively, findings here indicate near-source WBE as a rapid, unbiased and scalable tool for disease outbreak detection and for mapping disease flow between prisons and their surrounding communities, advocating its integration into routine health-security frameworks for custodial and other high-density settings.
Silicon and methionine enhance cowpea water stress tolerance
Abstract This study investigated whether foliar application of silicon (Si) and methionine (Met) can modulate the biochemical metabolism and growth of cowpea ‘BRS Exuberante’ during water restriction and rehydration cycles, based on the hypothesis that these elicitors could improve physiological recovery after water stress. Considering the above, the experiment was conducted in a completely randomized design, in a 2 × 4 factorial scheme, with four replications. The factors studied were: water stress period and rehydration period. In addition, the following foliar doses of the elicitors were applied: control, 300 mg L-1 of Si, 890 mg L-1 of Met, and the combination of both, 300 mg L-1 of Si + 890 mg L-1 of Met. The results that positively impacted the mitigation of water stress observed in the presence of silicon were more related to growth, although they also reflected improvements in biochemical metabolism. Methionine, on the other hand, was associated with changes in biochemical aspects that benefited growth. In both cases, the improvements that occurred during water restriction were what enabled greater recovery potential after rehydration. Both attenuating agents proved effective in inducing tolerance to certain physiological characteristics. Therefore, their use represents a promising alternative to strengthen the tolerance mechanisms of cowpea, especially by stimulating its ability to recover from stress after rehydration.