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Quantitative classification and ordination are instrumental in improving our understanding of plant community patterns and facilitating effective conservation efforts in national mountain ecosystems worldwide. However, there has been a lack of relevant research focused on arid and semi-arid mountain ecosystems. This study aims to address this gap by investigating the Ningxia Helan Mountain National Nature Reserve (located in Northwest China). We conducted a comprehensive study on the patterns of plant communities and their association with environmental factors across a broad elevation range from 1200 m a.s.l. to 2600 m a.s.l. Our findings revealed the presence of 121 angiosperm species across 41 families, with vegetation classified into six distinct groups through two-way indicator species analysis (TWINSPAN) along the elevational gradient. Notably, the communities of Ulmus, Prunus, and Stipa in the middle elevation range exhibited the highest Shannon–Wiener (SW) and Simpson (SN) diversity indices, and these indices followed a single-peak pattern with increasing elevation. Canonical correspondence analysis (CCA) further revealed six distinct yet interrelated plant communities, revealing elevation (ELE) and the biological aridity index (BK) as the most influential environmental factors influencing plant communities' distribution. This understanding is critically important for biodiversity conservation and the management of ecosystems in arid and semi-arid mountain ecosystems. [ABSTRACT FROM AUTHOR]

Endophytic fungi can be used as a source of herbal antioxidants to overcome the limitations of low yield and lengthy growth cycles associated with using plants as raw materials for antioxidant production. Papaya fruit is often susceptible to infection by Colletotrichum gloeosporioides after harvest, leading to postharvest rot. Endophytic fungi were extracted with ethyl acetate, and the initial screening concentration was 100 mg/L. Seven strains were identified, with scavenging rates exceeding 50% and strong antioxidant activity. The IC50 values in DPPH and ABTS free radical scavenging assays ranged from 19.72 to 84.06 mg/L and from 14.34 to 64.63 mg/L, respectively. Strain Y17 exhibited robust antioxidant activity (IC50 < 20 mg/L) and was identified as Penicillium rolfsii (MT729953) through ITS sequencing. Treatment of papaya fruit wounds with a fermentation broth of strain Y17 significantly inhibited the infection and colonization of anthracnose pathogens, resulting in a slowed disease incidence rate. This promoted the activity of protective enzymes, such as CAT, POD, and SOD, in the papaya fruit and slowed down the rate of MDA accumulation. This strain, which was found to have antioxidant activity in this study, has the potential to control anthracnose in papaya and has value in terms of further development and utilization. [ABSTRACT FROM AUTHOR]

Amid the escalating global demand for raw materials, the gradual exhaustion of terrestrial mineral resources, and the rise in extraction costs and energy consumption, the development of deep-sea mineral resources has become a focal point of international interest. The pipeline lifting mining system, distinguished by its superior mining efficiency and minimized environmental impact, now accounts for over 50% of the total energy consumption in mining operations. Serving as the "heart" of this system, the deep-sea lifting pump's comprehensive performance (high pressure tolerance, non-clogging features, elevated lift capacity, wear resistance, corrosion resistance, and high reliability, etc.), is critical to transport efficiency, operational stability, and lifespan of the mining system. As a mixed transport pump for solid and liquid media under extreme conditions, its internal flow structure is exceedingly complex, incorporating gas–liquid–solid multiphase flow. A precise understanding of its internal flow mechanisms is essential for breaking through the design limitations of deep-sea lifting pumps and enhancing their operational stability and reliability under various working conditions and multiphase media, thereby providing technical support for advancing global marine resource development and offshore equipment upgrades. This paper comprehensively reviews the design theory, optimization methods, numerical simulations, and experimental studies of deep-sea lifting pumps. It discusses the application of various design optimization techniques in hydraulic lifting pumps, details the multiphase flow numerical algorithms commonly used in deep-sea lifting pumps along with their modified models, and summarizes some experimental methodologies in this field. Lastly, it outlines the forthcoming challenges in deep-sea lifting pump research and proposes potential directions to promote the commercial development of deep-sea mining, thereby offering theoretical and engineering support for the development of deep-sea mining slurry pumps. [ABSTRACT FROM AUTHOR]

This study investigates covert communication in multi-sensor systems employing Intelligent Reflecting Surfaces (IRSs). Different from previous works, we focus on optimizing transmission amplitudes and phase angles for a 2-BPSK codebook in the presence of asymmetric noise over complex Gaussian channels. We adopt KL divergence as a covertness constraint and mutual information as a metric for transmission rate. We employ Taylor series expansion to approximate KL divergence and mutual information. Leveraging these approximations, we derive optimal phase angles through a proposed gradient descent algorithm. The numerical simulations validate the effectiveness and precision of our Taylor approximation method. Through validation in different scenarios, our algorithm demonstrates robust convergence, deriving all optimal phase angles. Comparing initial phase angles from prior works to those obtained via our algorithm, we observe a higher covert transmission rate. [ABSTRACT FROM AUTHOR]

As an energy harvesting device, the newly emerged thermocell has attracted great interest. However, it requires an additional energy storage device to complete a functional recycling system. As the core part of energy harvesting and storage devices, the design of electrodes with both high thermoelectric and electrochemical conversion efficiencies is particularly important. Herein, a high‐performance thermocell and supercapacitor device are constructed by employing the same mix‐phase MoSe2‐NiSe/NF electrode for both energy harvesting and storage. The thermocell exhibits an enhanced Seebeck coefficient of −1.69 mV K−1 and a superior output of 0.58 mW m−2 K−2 for low‐grade heat harvesting. Meanwhile, the supercapacitor device shows a great energy density of 54 Wh kg−1 at a power density of 806 W kg−1 and excellent cycling stability with a 92.8% retention rate after 50 000 cycles. This work offers a universal approach for the rational design of synergistic electrode materials to simultaneously achieve high‐energy harvesting and storage devices and lays a foundation for the recycling system of thermoelectric harvesting, conversion, and storage. [ABSTRACT FROM AUTHOR]

In order to solve the blockage effect and energy dissipation phenomenon caused by cavitation in the low-pressure vortex core region, this paper analyzes the spatial evolution of vorticity intensity and turbulent kinetic energy intensity under different cavitation conditions based on the Wray–Agarwal (WA) model. First, the tip leakage flow characteristics are studied, the evolution of vorticity and vorticity intensity is analyzed, then the distribution of turbulent kinetic energy distribution in the blade tip region is studied, and finally, the vorticity transport characteristics of the tip region are analyzed. It is found that the tip leakage rate is less affected by the vortex cavitation of the tip leakage, and there is a strong interaction between the leakage flow at the tip leading edge and the trailing edge, and the separation vortices and low-speed regions formed in the end-wall region cause blockage of the flow passage. Low pressure causes cavitation to cover most regions of the suction surface, inhibiting the formation and development of the tip leakage vortices. The distribution range of high turbulent kinetic energy region is almost the same as that of high-vorticity region, and there is a positive correlation between the two intensities. Severe cavitation causes the high turbulent kinetic energy region at the outlet of the flow passage to develop in the radial and axial directions of the impeller, which increases the turbulent dissipation and energy loss. The change of vorticity transport intensity caused by cavitation is mainly reflected in the expansion contraction term, and the Coriolis force term plays a dominant role in the vorticity transport process. This paper provides a reference for further improving the performance of mixed-flow pumps. [ABSTRACT FROM AUTHOR]

The railway industry has shown a strong interest in utilizing sustainable materials, including recycled materials and composites, in construction. Bamboo, as a highly renewable natural resource, has been proposed as a construction material for the railway industry. This material offers several advantages, such as high strength and durability, sustainability, low embodied energy, and ease of handling. It has been used in various construction materials like plywood, scrimber, laminates, and fibers. This paper aims to review the application of bamboo as a material in the railway industry and provide suggestions for its future use as railway sleepers. The mechanical properties of bamboo and its desirable features for sleeper construction, such as versatility, durability, low embodied energy and carbon footprint, lightweight, and ease of handling, are discussed. Bamboo-based products like plywood and scrimber can offer higher mechanical properties compared to traditional timber sleepers. Moreover, due to its rapid growth rate, bamboo is considered an environmentally friendly material. However, there are certain factors that limit the widespread deployment of bamboo in the railway industry. For instance, the lightweight nature of bamboo can reduce the lateral resistance of sleepers. Additionally, long-term performance studies and its performance in regions with varying weather conditions need to be further investigated. This review paper aims to promote the increased utilization of bamboo in the railway industry, contributing to the development of sustainable railway tracks. By considering the mechanical properties and advantageous characteristics of bamboo, it is possible to explore its potential as a viable and eco-friendly material for railway sleepers. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive investigation of the internal noise characteristics of a mixed-flow pump by combining computational fluid dynamics (CFD) and computational acoustics. The turbulent flow field of the pump is simulated using the unsteady SST k-ω turbulence model in CFD. The contributions of the volute, guide vanes, and impeller to the internal noise are analyzed and compared using the Lighthill theory, FW-H formula, and LMS Virtual Lab software for acoustic simulation. The research findings indicate that the energy of pressure fluctuations in the mixed-flow pump is predominantly concentrated at the blade passing frequency and its low-frequency harmonics. This suggests that the internal noise is mainly in the low-frequency range, with higher energy at the blade passing frequency and its harmonics. Under the 0.6Qdes flow condition, the flow inside the pump becomes more complex, resulting in higher sound pressure levels and sound power levels compared to higher flow conditions. However, for flow conditions ranging from 0.8Qdes to 1.2Qdes, the sound pressure levels gradually increase with increasing flow rate, with the sound pressure level at 1.0Qdes being nearly identical to that at 1.2Qdes. The analysis of sound power level spectra at different flow rates reveals that the distribution characteristics of internal vortex structures directly impact the hydrodynamic noise inside the mixed-flow pump. These research findings provide a significant theoretical basis for noise control in mixed-flow pumps. [ABSTRACT FROM AUTHOR]

Microalgae cultivation using wastewater is a combined process for pollutant removal and lipid production that has been widely studied in recent years. In this study, the effects of anaerobic membrane effluent (AME) and municipal wastewater (MW) ratios on microalgae growth and pollutant removal processes were investigated, and the lipid production properties were also explored. Results show that microalgae can grow in all AME/WW ratios, and a 40% AME content is the optimal condition for microalgal biomass accumulation (52.9 mg/L·d) and lipid production (0.378 g/L). Higher AME addition would inhibit microalgae growth. In addition, high ammonia (approximately 97%) and phosphate (around 90%) removal efficiencies can be achieved in all AME/WW ratio conditions, while the total nitrogen removal efficiencies decreased with the addition of AME. Total nitrogen and phosphate are the limiting factors in treating water to meet the requirements of the integrated wastewater discharge standard. This study provided a new method for anaerobic digestion and municipal wastewater treatment and also realized green energy production based on the sustainable development principles. [ABSTRACT FROM AUTHOR]

Sodium nitroprusside (SNP), as a nitric oxide donor, is widely used in postharvest fruit physiology and metabolism. Our previous study has indicated that SNP plays a crucial role in postharvest browning control of rambutan, but the molecular mechanism underlying this process is still unclear. In this research, we investigated the gene expression and function of postharvest rambutan in response to SNP during browning. We found 7336 differentially expressed genes (DEGs), among which 2206 were upregulated and 5130 were downregulated. Gene Ontology (GO) enrichment as well as Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed, and the real‐time quantitative PCR (qPCR) data were consistent with transcriptome data. The DEGs relevant to rambutan pericarp browning were mainly involved in anthocyanin biosynthesis, phenolic oxidation, reactive oxygen species (ROS) production, and energy supply. It was shown that SNP regulated the synthesis and degradation of anthocyanins, accumulation of phenols, level of ROS and energy metabolism to suppress the postharvest browning of rambutan. Also, one WRKY transcription factor involved in ROS metabolism was observed to be differentially regulated. These findings add to our insights into the molecular mechanisms of the SNP‐induced browning delays of rambutan, which has implications for subsequent studies on molecular mechanisms of fruit browning. [ABSTRACT FROM AUTHOR]

Drought stress severely limits crop growth and yield. With the atmospheric CO2 constantly increasing, plants will be affected by multiple effects of drought and increased CO2 in the future. Abscisic acid (ABA) plays vital roles in plant stress tolerance, especially drought stress. However, little is known about the effects of elevated CO2 concentration (e[CO2]) and exogenous ABA in cucumber (Cucumis sativus L.) response to drought stress. In the present study, we investigated the effects of e[CO2] and exogenous ABA on the drought tolerance of cucumber seedlings under the simulated drought stress induced by 5% polyethylene glycol 6000. The experiment was a split-plot design, in which the main factor was CO2 concentrations; atmospheric and elevated CO2 concentrations (~400 and 800 ± 40 μmol mol−1, respectively). The subplot factor was the combinations of exogenous ABA and its synthesis inhibitor sodium tungstate (Na2WO4); deionized water (control), 20 μM ABA, 2 mM Na2WO4, and 2 mM Na2WO4 + 20 μM ABA, which were applied to plant leaves. The results showed that compared with exogenous ABA application only, e[CO2] combined with exogenous ABA significantly increased the biomass, chlorophyll content, and net photosynthetic rate (Pn) of cucumber seedlings under drought stress. Meanwhile, e[CO2] and exogenous ABA were more efficient in reducing the contents of reactive oxygen species and malondialdehyde, promoting the accumulation of proline, soluble sugar, soluble protein, free amino acid, ascorbic acid, and glutathione. The ratios of ascorbic acid/dehydroascorbic acid (ASA/DHA), glutathione/oxidized glutathione (GSH/GSSG), as well as the activities of antioxidant enzymes were increased. In conclusion, e[CO2] and exogenous ABA synergistically alleviated oxidative damage of drought stress on cucumber seedlings by increasing antioxidant enzyme activities and accelerating the ASA–GSH cycle in cucumber seedlings, which in turn improved the drought tolerance of cucumber seedlings, and provided theoretical and practical support for further studies on the alleviation of drought stress in protected horticulture. [ABSTRACT FROM AUTHOR]

In this work, Magnesium oxide (MgO) adsorbents were synthesized by coprecipitation method via natural bischofite (MgCl2 ⋅ 6H2O, ≥96 wt %) as magnesium source, two different morphologies of MgO nanomaterials, flower‐spheres‐like (MgO−S1) and lamellas‐like (MgO−L1), were successfully synthesized by control of synthesis conditions. The adsorption experimental results showed on Congo Red (CR) dye that both MgO−S1 and MgO−L1 exhibit outstanding adsorption performance with a high adsorption quantity (about 2000 mg ⋅ g−1). Langmuir was the most suitable model to describe the adsorption isotherm. The adsorption kinetics of CR are in accord with the pseudo‐second‐order kinetics (PSO). As a control, flower‐spheres‐like (MgO−S2) and lamellas‐like (MgO−L2) were synthesized by commercial MgCl2 ⋅ 6H2O, and their adsorbing performance on CR dye in wastewater was studied. The results show that MgOs prepared by different Mg resources took on exactly the same shape and nearly the same adsorption properties. [ABSTRACT FROM AUTHOR]

Simple Summary: Acute myeloid leukemia (AML), especially the FLT3-ITD mutation subtype, has a poorer prognosis and higher risk of recurrence, which seriously threatens human health. Ferroptosis, an iron-dependent regulated cell death, is involved in the development and progression of AML. The mechanism by which circRNAs regulate the pathogenesis and prognosis of FLT3-ITD mutant-type AML through ferroptosis-related genes (FerRGs) remains unclear. In the present study, we aimed to decipher the pathogenic role of circRNAs in AML with FLT3-ITD mutation. Encouragingly, we discovered a circRNA, hsa_circ_0015278, that regulates ferroptosis-related genes by sponging miRNAs to promote FLT3-ITD AML progression. Furthermore, ferroptosis-related genes with prognostic value contribute to FLT3-ITD AML progression by regulating the tumor microenvironment. In conclusion, we constructed a ceRNA regulatory network involving hsa_circ_0015278/miRNAs/FerRGs, and the hsa_circ_0015278 signaling axis contributes to the identification of potential diagnostic and prognostic biomarkers and provides new insight into the pathogenesis and therapeutic targets of AML with FLT3-ITD mutation. AML with the FLT3-ITD mutation seriously threatens human health. The mechanism by which circRNAs regulate the pathogenesis of FLT3-ITD mutant-type AML through ferroptosis-related genes (FerRGs) remains unclear. Differentially expressed circRNAs and mRNAs were identified from multiple integrated data sources. The target miRNAs and mRNAs of the circRNAs were predicted using various databases. The PPI network, ceRNA regulatory network, GO, and KEGG enrichment analyses were performed. The "survival" and the "pROC" R packages were used for K-M and ROC analysis, respectively. GSEA, immune infiltration analysis, and clinical subgroup analysis were performed. Finally, circRNAs were validated by Sanger sequencing and qRT-PCR. In our study, 77 DECircs-1 and 690 DECircs-2 were identified. Subsequently, 11 co-up-regulated DECircs were obtained by intersecting DECircs-1 and DECircs-2. The target miRNAs of the circRNAs were screened by CircInteractome, circbank, and circAtlas. Utilizing TargetScan, ENCORI, and miRWalk, the target mRNAs of the miRNAs were uncovered. Ultimately, 73 FerRGs were obtained, and the ceRNA regulatory network was constructed. Furthermore, MAPK3 and CD44 were significantly associated with prognosis. qRT-PCR results confirmed that has_circ_0015278 was significantly overexpressed in FLT3-ITD mutant-type AML. In summary, we constructed the hsa_circ_0015278/miRNAs/FerRGs signaling axis, which provides new insight into the pathogenesis and therapeutic targets of AML with FLT3-ITD mutation. [ABSTRACT FROM AUTHOR]

The evolutionary success of heat recovery technology plays an important role in global sustainable energy solutions. Low-grade heat (below 200 °C) from solar radiation, industry, and the human body is usually discarded without any recovery effort. The ever-increasing energy crisis has motivated the development of high-performance thermoelectric generators to recover this low-grade heat. Compared to solid-state thermoelectric devices, the newly emerged redox-induced thermocells based on ion transport have provided another cheap, flexible, and scalable way for directly converting thermal energy into electrical energy. Therefore, we provide a comprehensive description of this emerging and promising system in this review. First, the background and underlying fundamentals are provided. The subsequent sections summarize the process regarding their electrolytes, electrode materials, and separators. Thereafter, cell configuration, integrated devices, and their applications such as power supply, temperature sensing, heat removal and recovery, and photothermal seawater desalination are emphasized. Finally, we highlight the future challenges and opportunities for high-performance redox-induced thermocells. [ABSTRACT FROM AUTHOR]

The Minisci alkylation of N‐heteroarenes with unactivated alkanes under external oxidant‐free conditions provides an economically attractive route to access alkylated N‐heteroarenes but remains underdeveloped. Herein, a new electrophotocatalytic strategy to access alkyl radicals from strong C(sp3)−H bonds was reported for the following Minisci alkylation reactions in the absence of chemical oxidants. This strategy realized the first example of cerium‐catalyzed Minisci alkylation reaction directly from abundant unactivated alkanes with excellent atom economy. It is anticipated that the general design principle would enrich catalytic strategies to explore the functionalizations of strong C(sp3)−H bonds under external oxidant‐free conditions with H2 evolution. [ABSTRACT FROM AUTHOR]

Herein, a series of hydroxy-substituted cyclic chalcone derivatives 1–3 are synthesized. Bulk single crystals with bright multicolor emission are cultivated and their molecular packing structures are deeply investigated. The hydroxyl substitution endows these compounds with intrinsic enol–keto tautomerism character. Interestingly, owing to the conjugation effect and intramolecular hydrogen bond, the enol form is more stable than the keto form and thus dominant in solution. And this also leads to pure enol structure in the crystalline state. Moreover, it is found that enol–keto tautomerism is affected to an extent by the solvents and temperature. Increasing the temperature or solvent polarity is conducive to the keto structure. Theoretical calculations are well consistent with the experimental result, which further reveals the evolvement of enol/keto structures. Additionally, this type of chalcone displays high potential as a multifunctional fluorescent probe as demonstrated by cell imaging and apoptosis analysis. These findings would not only have great importance on disclosing the structure–property relationship of chalcone-based organic fluorophores but also provide a simple strategy for designing multicolored single crystals. [ABSTRACT FROM AUTHOR]

Chelate induction of organic acids has been recognized to enhance metal uptake and translocation in plants, but the underlying mechanism remains unclear. In this study, seedlings of Salix variegata were hydroponically exposed to the combinations of Cd (0 and 50 μM) and three exogenous organic acids (100 μM of citric, tartaric, or malic acid). Plant biomass, antioxidant enzymes, non-protein thiol compounds (NPT) content, and the expression of candidate genes associated with Cd accumulation and tolerance were determined. Results showed that Cd significantly inhibited plant biomass but stimulated the activity of antioxidant enzymes in the roots and leaves, while the lipid peroxidation increased as well. Respective addition of three organic acids greatly enhanced plant resistance to oxidative stress and reduced the lipid peroxidation induced by Cd, with the effect of malic acid showing greatest. The addition of organic acids also significantly increased the content of glutathione in the root, further improving the antioxidant capacity and potential of phytochelatin biosynthesis. Moreover, Cd induced the expression level of candidate genes in roots of S. variegata. The addition of three organic acids not only promoted the expression of candidate genes but also drastically increased Cd accumulation in S. variegata. In summary, application of citric, tartaric, or malic acid alleviated Cd-imposed toxicity through the boost of enzymatic and non-enzymatic antioxidants and candidate gene expression, while their effects on Cd tolerance and accumulation of S. variegata differed. [ABSTRACT FROM AUTHOR]

Chalcone single crystals 1–2 with red emission and photodimerization-triggered hopping behavior are designed via fine-tuning the substituent, and their distinctively different emission behavior is attributed to the molecular packing effect as demonstrated by single crystal structure analysis and theoretical calculations. [ABSTRACT FROM AUTHOR]

Thermally regenerative electrochemical cycles (TRECs) have drawn plenty of attention recently as an efficient and low-cost approach to convert heat to electricity. In this work, we report the application of cobalt hexacyanoferrate (CoHCF)-based materials in TRECs. When the battery is charged at a high temperature (TH) and discharged at a low temperature (TL), the discharge voltage is higher than the charge voltage due to the dependence of battery voltage on temperature, and thus low-grade heat can be converted into electricity. The temperature coefficient and specific heat of the material determine the energy conversion efficiency of the battery. When complexed with helical carbon nanotubes (HCNTs), the CoHCF/HCNTs show a higher absolute temperature coefficient and lower specific heat than pure CoHCF. Consequently, the heat-to-electricity conversion efficiency is greatly increased. It is suggested that moderately changing the temperature coefficient and specific heat is an effective strategy to further improve thermogalvanic performance of CoHCF-based materials. [ABSTRACT FROM AUTHOR]

As a conventional strategy to modulate the structure and properties of inorganic single crystals, hydration/solvation is rarely found to function in pure organic single crystal. Herein, we report chalcone single crystals with CHCl3-dependent emission color and jumping behavior. Two crystals: a pure crystal phase (1) with green-yellow emission and a CHCl3-containing co-crystal phase (1•2CHCl3) with orange-red emission were constructed by fine-controlling the crystallization conditions. The special halogen bond network in the crystal packing structure effectively narrows the bandgap and thereby redshift the emission of 1•2CHCl3. 1•2CHCl3 would revert to 1 together with emission color change when losing CHCl3. These findings are similar to the effect of H2O in hydrated inorganic crystals. Notably, owing to a special pre-organized "molecular pair" structure for [2 + 2] cycloaddition, the pure crystal phase 1 exhibits violently photo-induced jumping phenomenon, indicating large potentials in intelligent devices. This work would overturn the previous perception that the structurally simple solvent molecules without conjugation cannot greatly affect the structure and properties of pure organic single crystals and provide a new strategy to construct multi-colored organic fluorescent crystals. [ABSTRACT FROM AUTHOR]

Organic acids are critical as secondary metabolites for plant adaption in a stressful situation. Oxalic acid, tartaric acid, and malic acid can improve plant tolerance under waterlogged conditions. Two prominent woody species (Taxodium distichum-Swamp cypress and Salix matsudana-Chinese willow) have been experiencing long-term winter submergence and summer drought in the Three Gorges Reservoir. The objectives of the present study were to explore the responses of the roots of two woody species during flooding as reflected by root tissue concentrations of organic acids. Potted sample plants were randomly divided into three treatment groups: control, moderate submergence, and deep submergence. The concentrations of oxalic acid, tartaric acid, and malic acid in the main root and lateral roots of the two species were determined at four stages. The results showed that T. distichum and S. matsudana adapted well to the water regimes of the reservoir, with a survival rate of 100% during the experiment period. After experiencing a cycle of submergence and emergence, the height and base diameter of the two species showed increasing trends. Changes in base diameter showed insignificant differences between submergence treatments, and only height was significant under deep submergence. The concentrations of three organic acids in the roots of two species were influenced by winter submergence. After emergence in spring, two species could adjust their organic acid metabolisms to the normal level. Among three organic acids, tartaric acid showed the most sensitive response to water submergence, which deserved more studies in the future. The exotic species, T. distichum, had a more stable metabolism of organic acids to winter flooding. However, the native species, S. matsudana, responded more actively to long-term winter flooding. Both species can be considered in vegetation restoration, but it needs more observations for planting around 165 m above sea level, where winter submergence is more than 200 days. [ABSTRACT FROM AUTHOR]

The coordinated effects of CO 2 enrichment and drought stress on cucumber leaves have attracted increasing research attention, but few studies have investigated the effects of CO 2 enrichment on the root system under drought stress. So we analyzed the morphological parameters, hydraulic conductivity, aquaporin-related gene expression, and endogenous phytohormone contents in roots of cucumber seedlings cultured under different CO 2 concentrations (approximately 400 and 800 ± 40 μmol mol−1) and drought stresses simulated by polyethylene glycol 6000 (0%, 5%, and 10%). The results showed that under drought stress, regardless of the CO 2 concentration, the root biomass and hydraulic conductivity decreased, the contents of auxin (IAA), zeatin nucleoside (ZR), and gibberellin (GA) decreased, the abscisic acid (ABA) content and the transcript levels of the aquaporin-related genes CsPIP2-4 increased, and the transcript levels of the aquaporin-related genes CsPIP2-5 and CsPIP2-7 decreased compared with no drought stress. Under moderate drought stress, CO 2 enrichment decreased ABA content and the transcript level of CsPIP2-4 , increased root biomass and GA content and the transcript level of CsPIP2-7 , improved contribution rate of cell-to-cell water transport (mediated by aquaporins) and roots hydraulic conductivity. In summary, drought stress changed the water transport capacity of the roots and inhibited the growth of cucumber seedlings. CO 2 enrichment regulated phytohormone contents and aquaporin-related gene expression, maintained the normal contribution rate of cell-to-cell water transport, and improved the root biomass and hydraulic conductivity, thereby alleviated the negative effects of drought stress on cucumber seedlings. • Drought stress decreased the cucumber Lp r , the transcript levels of CsPIP2-5 and CsPIP2-7. • CO 2 enrichment increased the GA content while decreased ABA content. • CO 2 enrichment increased the transcript levels of CsPIP2-7 , while decreased the transcript levels of CsPIP2-4. • CO 2 enrichment improved Lp r , enhanced water absorption and transport capability of cucumber seedlings. [ABSTRACT FROM AUTHOR]

Carbon dioxide is one of the most important anthropogenic greenhouse gases. We previously confirmed that elevated [CO 2 ] alleviated the negative consequences of drought stress to cucumber seedlings, but the physiological mechanism remains unknown. We investigated the morphological and physiological characteristics as well as iTRAQ-based proteomics analyses in this study under different combinations [CO 2 ] (400 and (800 ± 20) μmol·mol−1) and water conditions (no, moderate and severe drought stress simulated by polyethylene glycol 6000). The results showed: (1) elevated [CO 2 ] significantly increased plant height, stem diameter, leaf area and relative water content (RWC) under drought stress; (2) drought stress significantly increased J and K peaks of the chlorophyll a fluorescence transient, indicating the damage of photosynthetic electron transport chain, while elevated [CO 2 ] decreased them especially under moderate drought condition; (3) iTRAQ-based proteomics analyses indicated that elevated [CO 2 ] increased the abundance of psbJ and the PSI reaction center subunit VI-2 in seedlings exposed to moderate drought stress; (4) the abundance of uroporphyrinogen decarboxylase 2 and tetrapyrrole-binding protein decreased in response to elevated [CO 2 ] under severe drought condition; (5) elevated [CO 2 ] regulated the expression of chloroplast proteins such as those related to stress and defense response, redox homeostasis, metabolic pathways. In conclusion, elevated [CO 2 ] enhanced the efficiency of photosynthetic electron transport, limited the absorption of excess light energy, enhanced the ability of antioxidant and osmotic adjustment, and alleviated the accumulation of toxic substances under drought stress. These findings provide new clues for understanding the molecular basis of elevated [CO 2 ] alleviated plant drought stress. • Elevated CO 2 concentration reportedly mitigated damages due to drought stress, but the physiological mechanism remains unknown. • The result showed that elevated [CO 2 ] increased the abundance of psbJ and the PSI reaction center subunit VI-2 in seedlings exposed to moderate drought stress, and decreased the abundance of uroporphyrinogen decarboxylase 2 and tetrapyrrole-binding protein under severe drought condition. • E[CO 2 ] alleviate cucumber drought stress to some extents by regulating expression of chloroplast proteins such as those related to photosynthesis, pigment biosynthesis, stress and defense response, redox homeostasis, metabolic pathways. • E[CO 2 ] down-regulated pigment biosynthesis under drought conditions, which decreased the absorption of excess light energy, thus minimizing the effects of reactive oxygen species and photodamage induced by drought stress. [ABSTRACT FROM AUTHOR]

The effects of CO 2 enrichment on water balance and nitrogen (N) assimilation in cucumber (Cucumis sativus L. cv. Jinyou No.35) seedlings under salt stress were investigated. Two-way randomized block design was used: the main treatment consisted of two [CO 2 ] levels, ambient and enriched (400 and 800 ± 40 μmol mol−1, respectively), and the minor treatment consisted on two salinity treatment levels, 0 and 80 mmol L−1 NaCl. The results showed that, under the experimental conditions, enriched [CO 2 ] and salt stress significantly inhibited the N assimilation process in cucumber leaves; however, enriched [CO 2 ] had no effect on the nitrate (NO 3 −) reduction or ammonium (NH 4 +) assimilation of leaves under salt stress, inhibiting only the transamination. Moreover, enriched [CO 2 ] increased the plasma membrane H+-ATPase activity, vacuolar membrane H+-ATPase activity and root hydraulic conductivity under salt stress, thereby increasing the ion selective absorption and water absorption capacity. To a certain extent, enriched [CO 2 ] promoted the accumulation of K+ in plants, which significantly reduced the Na+/K+ ratio; moreover, the enrichment ultimately improved the water state conditions and helped to maintain the ion balance in plants under stress, ensuring normal enzymatic activity. • Elevated [CO 2 ] increased the water absorption capacity. • Elevated [CO 2 ] increased the ion selective absorption. • Under the experimental conditions, enriched [CO 2 ] had no effect on the nitrate reduction or ammonium assimilation of leaves under salt stress. [ABSTRACT FROM AUTHOR]

[Display omitted] • A hierarchical ternary structure of FNPCN is rationally designed. • Obvious suppression on heat release is observed by incorporating FNPCN. • Marked hinderances on toxic CO and HCN emissions are found by using FNPCN. • Flame retardancy comparison with reported works confirms the meliority of FNPCN. High fire hazard of generating a great deal of heat and toxic volatiles has been deemed as notorious issue of thermoplastic polyurethane (TPU), severely impeding its practical usage. Hence, a hierarchical ternary structure (FNPCN) based on NiAl LDH anchored phosphorus-doped g-C 3 N 4 dotted with Fe 3 O 4 nanoparticles is rationally designed as flame retarded additive for TPU. Specifically, by adding 1.0 wt% FNPCN, the obvious reductions of 30.9% and 21.8% in peak heat release rate and total heat release are obtained, suggesting the suppressed heat release. Meanwhile, a marked decrease of 31.9% in peak smoke production rate is discovered, implying the reduced fire toxicity. Moreover, the direct evidence for hindered releases of toxic CO and HCN gases is provided by TG-IR spectra. These results jointly corroborate the efficacy of FNPCN in impairing the fire hazard of TPU, originating from its physical barrier and chemical catalyst characters. This work may shed a light on the designing of hierarchical ternary structure, optimizing their prospects in polymer-matrix composite and other areas. [ABSTRACT FROM AUTHOR]