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To explore the possible novel microRNA (miRNA) regulatory pathways in Zhengmai 1860, a newly cultivated drought-tolerant wheat (Triticum aestivum L.) cultivar, miRNA transcriptome sequencing of the flag leaves of Zhengmai 1860, drought-sensitive variety Zhoumai 18, and drought-resistant variety Bainong 207 was performed during the grain filling stage. We also observed changes in the chloroplast ultrastructure, phytohormone levels, and antioxidant- and photosynthesis-related physiological indicators in three wheat varieties. The results showed that the flag leaves of the drought-tolerant variety Zhengmai 1860 had higher chlorophyll contents and net photosynthetic rates than those of Zhoumai 18 under drought stress during the grain filling stage; in addition, the chloroplast structure was more complete. However, there was no significant difference between Zhengmai 1860 and Bainong 207. MiRNA transcriptome analysis revealed that the differential expression of the miRNAs and mRNAs exhibited variable specificity. The KEGG pathway enrichment results indicated that most of the genes were enriched in the MAPK signaling pathway, plant hormone signal transduction, photosynthetic antennae protein, and amino acid and carbohydrate metabolism. In the drought-tolerant cultivar Zhengmai 1860, tae-miR408 was targeted to regulate the allene oxide synthase (AOS) gene, inhibit its expression, reduce the AOS content, and decrease the synthesis of jasmonic acid (JA) and abscisic acid (ABA). The results of this study suggest that Zhengmai 1860 could improve the photosynthetic performance of flag leaves by inhibiting the expression of genes involved in the JA pathway through miRNAs under drought conditions. Moreover, multiple miRNAs may target chlorophyll, antioxidant enzymes, phytohormone signal transduction, and other related pathways; thus, it is possible to provide a more theoretical basis for wheat molecular breeding. [ABSTRACT FROM AUTHOR]

To provide molecular‐scale insight into the structural evolution from tris(methylamino)borane to boron nitride (BN) fiber during the chemical thermal‐treating process, polymeric green fiber is cured in hot synthetic air at 300°C and then treats to 400, 600, 800, and 1000°C in ammonia. The chemical composition and structure of the volatile compounds and residual products are analyzed during the pyrolysis process for the polymeric green fiber. It is demonstrated that oxygen can be used to cure polymeric green fiber rapidly under the premise of ensuring a final fiber content of less than 1 wt% carbon and 2 wt% oxygen while maintaining the fiber tensile strength at 1000°C. The molecular structure evolution during the pyrolysis process for polymeric green fiber after oxygen curing is determined. Specifically, in hot synthetic air, introducing oxygen and releasing methylamine generates a B–O six‐membered ring structure in the polymer in the first stage. Then, the removal of methyl results in the formation of a B–N–O network in hot ammonia. Afterward, nitridation of the B–O six‐membered ring promotes the evolution of the B–N six‐membered ring structure with the release of water and carbon dioxide. Finally, the growth and rearrangement of the BN structure are achieved. [ABSTRACT FROM AUTHOR]

Psb28 is a soluble protein in the photosystem II (PSII) complex, but its role in the drought stress response of wheat remains unclear. Here, we functionally characterized the TaPsb28 gene, which positively regulates drought tolerance in wheat. When the full-length 546-bp TaPsb28 cDNA was transferred into Arabidopsis thaliana, it was located in the guard cell chloroplast around the stroma. Overexpression of TaPsb28 conferred drought tolerance, as exhibited by the increases in the survival rate. Transgenic plants maintained lower MDA content and higher chlorophyll content by inducing chlorophyll synthase (ChlG) gene transcription. The content of abscisic acid (ABA) and zeatin increased significantly in wild-type (WT) plants under drought stress, and the transcriptional expression levels of RD22, dihydroflavonol 4-reductase (DFR) and anthocyanin reductase (ANR) genes were induced, thus enhancing the contents of endogenous cyanidin, delphinidin, and proanthocyanidins. However, in transgenic plants, although anthocyanins were further aggregated, the ABA increase was inhibited, zeatin was restored to the control level under drought stress, and stomatal closure was promoted. These findings indicate ABA and zeatin have opposite synergistic effects in the process of drought tolerance caused by TaPsb28 because only after the effect of zeatin is alleviated can ABA better play its role in promoting anthocyanin accumulation and stomatal closure, thus enhancing the drought tolerance of transgenic plants. The results suggest that overexpression of TaPsb28 exerts a positive role in the drought response by influencing the functional metabolism of endogenous hormones. The understanding acquired through the research laid a foundation for further in-depth investigation of the function of TaPsb28 in drought resistance in wheat, especially its relationship with anthocyanidin accumulation. [ABSTRACT FROM AUTHOR]

Summary: Genetically enhancing drought tolerance and nutrient use efficacy enables sustainable and stable wheat production in drought‐prone areas exposed to water shortages and low soil fertility, due to global warming and declining natural resources. In this study, wheat plants, exhibiting improved drought tolerance and N‐use efficacy, were developed by introducing GmTDN1, a gene encoding a DREB‐like transcription factor, into two modern winter wheat varieties, cv Shi4185 and Jimai22. Overexpressing GmTDN1 in wheat resulted in significantly improved drought and low‐N tolerance under drought and N‐deficient conditions in the greenhouse. Field trials conducted at three different locations over a period of 2–3 consecutive years showed that both Shi4185 and Jimai22 GmTDN1 transgenic lines were agronomically superior to wild‐type plants, and produced significantly higher yields under both drought and N‐deficient conditions. No yield penalties were observed in these transgenic lines under normal well irrigation conditions. Overexpressing GmTDN1 enhanced photosynthetic and osmotic adjustment capacity, antioxidant metabolism, and root mass of wheat plants, compared to those of wild‐type plants, by orchestrating the expression of a set of drought stress‐related genes as well as the nitrate transporter, NRT2.5. Furthermore, transgenic wheat with overexpressed NRT2.5 can improve drought tolerance and nitrogen (N) absorption, suggesting that improving N absorption in GmTDN1 transgenic wheat may contribute to drought tolerance. These findings may lead to the development of new methodologies with the capacity to simultaneously improve drought tolerance and N‐use efficacy in cereal crops to ensure sustainable agriculture and global food security. [ABSTRACT FROM AUTHOR]

Objective: Hypertension requires continuous and long‐term care to prevent associated complications. Chronic disease management mode (CDMM) was developed to improve patients' self‐management. We aimed to evaluate quality of care and clinical outcomes of CDMM versus routine care. Methods: 300 patients aged >30 years with primary hypertension were randomly allocated to the CDMM intervention group (n = 162) or the usual care control group (n = 138). CDMM comprised nursing consultations, telephone contact, online WeChat link, health education, and appropriate referrals during hospitalisation and after discharge. QLICD‐HY (V 2.0) scale was used to evaluate the quality of life. Care outcomes were biochemical parameters, body mass index, blood pressure levels, waist circumference, psychological indicators and quality of life assessed on admission (baseline) and one month post‐care for both groups. Data were collected and analysed using SPSS 20.0. Results: After one month, the intervention group had 6 mm Hg (95% CI: −5.12 to −9.08) lower SBP and 0.6 mM/L (95% CI: −0.52 to −0.68) lower LDL than the control group. In terms of improvements in BMI, UmAlb or waist circumference, there were no differences between both groups. The intervention group scored better on psychological indicators than controls (P < 0.05), and scores reflecting social and psychological function in the intervention group were significantly higher than scores at baseline, and higher than scores of controls after one month (P < 0.05). In the control group, there was no statistically significant difference between the scores at baseline and after one month. Conclusions: Under CDMM hypertension care, improvement of blood pressure and LDL was clinically significant. Intervention care further improves social and psychological function among participants with primary hypertension. [ABSTRACT FROM AUTHOR]

Batteries with lithium metal as anodes and gel polymer membranes as electrolytes are promising, because of their high energy densities and improved safety. To achieve metal battery energy densities that are comparable to liquid‐electrolyte batteries, ultrathin and lightweight gel electrolytes with wide electrochemical stability windows are desired. However, it is challenging to make gel polymer electrolyte membranes with comparable thicknesses to commercial polymer electrolyte separators (<20 μm), because of the porous configuration and increased risk of short‐circuiting cells. Here, we report on a 10 μm‐thick compacted gel polymer electrolyte (TCGPE), demonstrated to have a robust chemical interaction between SiO2 nanoparticles and poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP) chains that are activated via an in situ sol‐gel reaction. The developed TCGPE exhibits an extremely wide electrochemical stability window of 5.5 V vs. Li/Li+ and prevents the batteries from short‐circuiting even at a high current density of 1.0 mA cm−2. Moreover, Li/TCGPE/LiNi0.5Co0.2Mn0.3O2 shows an excellent capacity retention of 99.8 % after 180 cycles at 1 C rate. [ABSTRACT FROM AUTHOR]

With 7 figures and 2 tables Abstract Attempts have been made to transform C3 crops with C4 genes to improve the photosynthetic rate of C3 plants. In our study, a full-length cDNA for phosphoenolpyruvate carboxylase gene ( pepc) was isolated from Zea mays by PCR. The pepc gene was introduced into wheat plants ( Triticum aestivum) by particle bombardment transformation. The integration, transcription and expression of the pepc gene were confirmed by Southern blot, RT-PCR and Western blot analysis. Physiological studies showed that phosphoenolpyruvate carboxylase activity in the transgenic plants was 140% higher than that of the untransformed plants. The highest rate of photosynthesis in the transgenic plants was 31.95 μmol CO2/m2/s, which was 26% greater than the rate in untransformed plants. The light saturation point and carboxylation efficiency of pepc transgenic wheat were 20% and 22.57% higher, respectively, than those of untransformed wheat. As a result, the weight of seed per spike and thousand-grain weight were 0.23 g and 1.21 g higher than those of untransformed wheat. Our research will facilitate the further study of the function of the pepc gene in wheat plants. [ABSTRACT FROM AUTHOR]

This study assessed the effects of seven combinations of maize (Zea mays) genes phosphoenolpyruvate carboxylase (pepc), pyruvate phosphate dikinase (ppdk), and NADP-malic enzyme (nadp-me), on the photosynthesis of Arabidopsis. The photosynthetic rate, carboxylation efficiency, and shoot-dry-weight of Zmpepc (PC), Zmpepc + Zmppdk (PCK), Zmpepc + Zmnadp-me (PCM), and Zmpepc + Zmppdk + Zmnadp-me (PCKM) were significantly higher than those of the control wild-type (WT), with a trends to be PCKM > PCK > PC and PCM > WT. This indicated that Zmpepc was a prerequisite for improved photosynthetic performance; Zmppdk had a positive effect on Zmpepc , and the triple gene combination had the most significant synergistic effects. PCKM significantly enhanced activity of photosystem (PS)II (K, J phase) and PSI, light energy absorption (ABS/CSm) and conversion (TRo/ABS), and electron transfer (ETo/TRo). PCKM up-regulated 18 photosynthesis-related proteins, among which, 11 were involved in light reaction resulting in improved light-energy absorption and conversion efficiency, electron transfer, activity and stability of PSII and PSI, and the ATP and NADPH production. The remaining seven proteins were involved in dark reaction. The up-regulation of these proteins in PCKM improved the coordinated operation of light and dark reaction, increasing the photosynthesis and dry weight ultimately. These results also provide a promising strategy for the genetic improvement of the photosynthetic performance of C 3 crops by inserting major C 4 photosynthetic genes. • Arabidopsis was transformed with C 4 plant genes (Zmpepc , Zmppdk and Zmnadp-me). • Joint expression of the three C 4 plant genes significantly enhanced photosynthesis. • Eighteen proteins involved in photosynthetic process were up-regulated. • The light-energy absorption, conversion and CO 2 assimilation were all improved. • The overproduction of the metabolites of C 4 process may work as signals. [ABSTRACT FROM AUTHOR]

Wheat is one of the staple food crops worldwide and breeding for high yield wheat is critical to meet the need of increasing world population. To determine the factors that limit wheat yield potential in Henan province, China, 30 wheat cultivars that have been widely grown in Henan province since 1940s were evaluated for grain yield and related physiological traits. The results show that grain yield has been significantly increased since 1940s, with an annual genetic gain of 1.09%, and the increased yield after 1900s was attributed to the introduction of 1BL/1RS translocation. The significant yield increase mainly resulted from a significant increase in grain number per spike (GNPS), thousand kernel weight (TKW) and harvest index (HI), and a significant decrease in plant height due to utilization of semi-dwarfing genes. The genetic improvement of assimilate accumulation and translocation was mainly reflected by the improvement in post-anthesis assimilate accumulation (PoAAA) and post-anthesis transportion rate (PoATR) of pre-anthesis assimilates (PrAA), with genetic gains of 0.63% and 1.89%, respectively. The improvement of the PoAAA was closely related to an increase in net photosynthetic rates ( P n ) of flag leaves at anthesis and 20 days after anthesis, and leaf area index (LAI) at 20 days after anthesis; whereas the improvement of the PoATR of the PrAA was closely associated with the improvement of accumulation and redistribution of the assimilates accumulated in stems and sheaths. As yield increased, the source-sink ratio significantly decreased, reflecting that the source has been gradually becoming a limiting factor to grain yield increase. Therefore, diverse strategies should be adopted to improve biomass (source) in future wheat breeding to meet the need of continuous increasing in wheat yield. [ABSTRACT FROM AUTHOR]

This study assessed the responses of wild-type (WT) and transgenic Arabidopsis expressing seven combinations of maize ( Zea mays ) genes phosphoenolpyruvate carboxylase ( pepc ), pyruvate phosphate dikinase ( ppdk ), and NADP-malic enzyme ( nadp-me ) to high light. Our results showed that the net CO 2 assimilation rate ( P n ) and shoot dry weight of four of the transgenic Arabidopsis genotypes were significantly different from those of WT under high-light treatment, being in the order of Zmpepc+Zmppdk+Zmnadp-me (PC-K-M) > Zmpepc+Zmppdk (PC-K) > Zmpepc (PC), Zmpepc+Zmnadp-me (PC-M) > WT. The other genotypes did not differ from WT. This indicated that Zmpepc was essential for maintaining high photosynthetic performance under high light, Zmppdk had a positive synergistic effect on Zmpepc , and the combination of all three genes had the greatest synergistic effect. These four genotypes also maintained higher photosystem II (PSII) activity (K-phase, J-phase, RC/CSm), electron transfer capacity (J-phase), and photochemical efficiency (TRo/ABS), and accumulated less reactive oxygen species (O 2 · - , H 2 O 2 ) and suffered less damage to the membrane system (MDA) than WT under high light. Collectively, PC, PC-K, PC-M, and PC-K-M used most of the absorbed energy for CO 2 assimilation through a significantly higher P n , which reduced the generation of excess electrons in the photosynthetic apparatus, thereby reducing damage to the membrane system and PSII. This ultimately resulted in improved high-light tolerance. P n was the main reason for the significant difference in the high-light tolerance of the four genotypes. Joint expression of the three maize genes may be of great value in the genetic improvement of high-light tolerance in C 3 crops.