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【Objective】 To explore the effects of new composite hydrogel on the physiological characteristics of tobacco seedlings under drought stress, and to provide theoretical basis for alleviating the toxicity of drought stress to tobacco. 【Method】 A total of 10 treatments including CK control and three different hydrogels added at 0.1%, 0.5% and 0.9% of soil dry mass: commercial hydrogel HS, new composite hydrogel HM (polyvinyl alcohol-acrylic acid-molecular sieve hydrogel) and HB (polyvinyl alcohol-acrylic acid-biochar hydrogel) were designed by pot experiment to study the effects of new composite hydrogels on tobacco under drought stress The effects of the new composite hydrogels on biomass accumulation, root development, photosynthetic system and oxidative stress of tobacco under drought stress were investigated. 【Result】 Under the same dosage conditions, HM and HB treatments were effective in increasing the fresh mass, dry mass and total water content of tobacco under drought stress compared to HS treatment. Compared with CK, HM and HB treatments could increase the fresh mass by a maximum of 153.91% and 126.34%, respectively. Under the same dosage conditions, HM and HB treatments significantly increased the total root length, total root surface area, average root diameter, root tip number and root volume, and improved the root vigor of tobacco compared with HS treatments; photosynthetic parameters and SPAD values of tobacco increased significantly and improved leaf stomatal status; SOD (superoxide dismutase), POD (peroxidase) and CAT (catalase) activities and soluble protein amounts of tobacco increased and MDA (malondialdehyde) amounts decreased significantly, which enhanced the resistance of tobacco. 【Conclusion】 Adding 0.9% HM and HB hydrogels to soil dry weight can effectively reduce the impact of drought stress on tobacco and improve tobacco drought resistance.

【Objective】 Drought is the most common abiotic stress affecting agricultural production in most countries, and alleviating its detrimental effect is critical to safeguarding crop growth. The purpose of this paper is to compare the efficacy of water adsorption polymer in improving soil water retention and growth of tobacco seedlings. 【Method】 Water adsorption polymer particles with diameter in the range of 0.3~1.0 mm (T1), 1.0~2.5 mm (T2), and 2.5~4.75 mm (T3) were mixed with soil thoroughly prior to planning, respectively, with soil not being amended as the control (CK); plants in all treatments were under water stress. The field water capacity, water retention rate, as well as the growth and development of the tobacco seedlings were measured in each treatment. 【Result】 The field capacity maximized when the particle diameter was in the range of 2.5~4.75 mm, up 30.49% higher than that in the CK. Mixing soil with polymer particles with diameter in the range of 1.0~2.5 mm gave the highest soil water retention capacity. Soil amended by polymer particles with diameter in the range of 1.0~2.5 mm can effectively alleviate drought stress, promoting biomass accumulation in the plant. Soil amendment increased its total water content, relative water content and free water content in tobacco leaves by 4.93%, 24.35% and 11.81%, respectively, while reduced bound water, bound technique/free water, and water saturation deficit by 5.25%, 16.18%, and 63.51%, respectively. Compared with CK, soil amendment with the polymer also reduced the activities of SOD, POD, CAT, MDA, and soluble protein in the plant by 114.86%, 211.93%, 67.05%, and 273.29%, 27.73% respectively. 【Conclusion】 Amending the soil with water absorbent polymer particles with diameter in the range of 1.0~2.5 mm is most effective to improve the field capacity and water-retention capacity of the soil, effectively alleviating drought stress to tobacco seedlings.

Yb-doped Y2O3 stabilized ZrO2 (YbYSZ) coatings, developed through solution precursor plasma spraying (SPPS), are engineered to resist calcium–magnesium–alumino–silicate (CMAS) infiltration by leveraging their unique micro-nano structures. This provides superior anti-wetting properties, crucial for preventing CMAS penetration at high temperatures. The investigation focused on the structural and compositional changes in YbYSZ-SPPS coatings subjected to prolonged thermal exposure at 1300 °C. Results indicate that while the coatings undergo significant sintering, leading to densification and microstructural evolution, the elemental composition and phase stability remain largely intact after up to 8 h of heat treatment. Despite some reduction in CMAS resistance, the coatings maintained their overall protective performance, demonstrating the potential of SPPS coatings for long-term use in high-temperature environments where CMAS infiltration is a concern. These findings contribute to the development of more durable TBCs for advanced thermal protection applications. [ABSTRACT FROM AUTHOR]

Accurate estimation of pandemic likelihood in every US state of interest and at any time. Coronavirus disease 2019 (COVID‐19) is an infectious illness with a high potential for global dissemination and low rates of fatality and morbidity, placing some strains on national public health systems. This research intends to benchmark a novel technique, that enables hazard assessment, based on available clinical data, and dynamically observed patient numbers while taking into account pertinent territorial and temporal mapping. Multicentre, population‐based, and biostatistical strategies have been utilized to process raw/unfiltered medical survey data. The expansion of extreme value statistics from the univariate to the bivariate situation meets with numerous challenges. First, the univariate extreme value types theorem cannot be directly extended to the bivariate (2D) case,—not to mention challenges with system dimensionality higher than 2D. Assessing outbreak risks of future outbreaks in any nation/region of interest. Existing bio‐statistical approaches do not always have the benefits of effectively handling large regional dimensionality and cross‐correlation between various regional observations. These methods deal with temporal observations of multi‐regional phenomena. Apply contemporary, novel statistical/reliability techniques directly to raw/unfiltered clinical data. The current study outlines a novel bio‐system hazard assessment technique that is particularly suited for multi‐regional environmental, bio, and public health systems, observed over a representative period. With the use of the Gaidai multivariate hazard assessment approach, epidemic outbreak spatiotemporal risks may be properly assessed. Based on raw/unfiltered clinical survey data, the Gaidai multivariate hazard assessment approach may be applied to a variety of public health applications. The study's primary finding was an assessment of the risks of epidemic outbreaks, along with a matching confidence range. Future global COVID‐19/severe acute respiratory syndrome coronavirus 2 (SARS‐COV2) epidemic risks have been examined in the current study; however, COVID‐19/SARS‐COV2 infection transmission mechanisms have not been discussed. [ABSTRACT FROM AUTHOR]

A novel axially chiral all-hydrocarbon cyclo[7] (1,3-(4,6-dimethyl)benzene (CDMB-7) was designed and synthesized using atroposelective[2 + 5] cyclization through Suzuki–Miyaura coupling. CDMB-7 adopts an irregular bowl-like shape with C2 symmetry and exhibits two diastereoisomers in its crystallographic structure. The conformational isomers of CDMB-7 racemates remain stable at high temperatures (393 K). High-performance liquid chromatography (HPLC) confirmed that a single chiral isomer will spontaneously undergo racemization within 30 min at room temperature. This finding opens up possibilities for achieving adaptive chirality in all-hydrocarbon cyclo[7] m-benzene macrocycles. [ABSTRACT FROM AUTHOR]

This study focuses on investigating interfacial interactions and the adhesion mechanism of polymer-metal interfaces in nano-molding. Polyphenylene sulfide (PPS), polyamide 6 (PA6), and isotactic polypropylene (iPP) were chosen as candidate polymers, and aluminum (Al), and copper (Cu) were used as metal substrates. By establishing the metal matrix composed of a rectangular pit with length, width, and depth of 4.5, 4.5, and 2.0 nm, respectively, six paired polymer-metal interfacial systems in a cuboid of 7.5 * 7.5 * 11.5 nm, consisting of metal, polymer, and vacuum layer (from bottom to top) were constructed. Molecular dynamics simulations were performed to calculate interfacial interactions and bonding processes. Results showed that wall-slip behavior was pronounced in nano-molding. Viscoelasticity and polarity of the polymers played a crucial role in interfacial interactions, which guided the wall-slip behavior and greatly affected the bolt performance. PA6 and PPS were more suitable for molding than iPP on both Al and Cu substrates. PA6 showed the best filling and bonding performances, followed by PPS, while iPP revealed the poorest performances. The Cu substrate exhibited better anchor strength and filling rate than Al substrates with the same polymer. KEYWORDS adhesion, injection molding, interactions, molecular dynamics, 1 | INTRODUCTION The interest in manufacturing polymer-metal integration products by means of injection molding is increasing due to the advantages in productivity and cost effectiveness. [1-3] By combining metals [...]