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Umami substances can increase the overall taste of food and bring pleasure to people.

A lignin-first strategy is promising in lignin utilization to produce value-added aromatic compounds and their derivatives for achieving high efficiency. In this work, we explored the hydrogenolysis of cornstalk lignin in supercritical ethanol and investigated the effects of metal sites and acid sites during lignin-first fractionation. By comparison, the acid pretreatment of Ru/C catalysts significantly promotes the hydrogenolysis process, wherein Ru/C-acid (10) exhibits the best result with 42.9 wt% yield of monomer products (including aromatic monomers and hydrogenated monomers) at 260 °C, 3 MPa H2 for 4 h. Catalysts were measured by BET, TEM and NH3-TPD characterizations, and the hydrogenolysis products were compared by GC-MS, GPC, element analysis and FT-IR characterizations. The analysis results indicate that the active metal site and the abundant acid site are mainly responsible for the efficient lignin hydrogenolysis performance, and these two factors present a significant effect to achieve a high monomer yield.

This study aimed to investigate the optimal frozen embryo transfer (FET) strategy in recurrent implantation failure (RIF) patients with three consecutive failed cleavage embryo implantations. A retrospective analysis of FET cycles performed in our IVF center from January 2018 to August 2020. The FET cycles were classified into three groups according to their FET strategies: thawed day 3 embryo transfer (D3 FET group) (n = 52), thawed blastocyst transfer (D5 FET group) (n = 166), and extended culturing of frozen-thawed day 3 embryos to day 5 blastocysts transfer (D3-5 FET group) (n = 58). The biochemical, clinical pregnancies, implantation, abortion, multiple pregnancy, and live birth were analyzed and compared among the three groups. A total of 43.8% of vitrified-thawed cleavage embryos developed into blastocysts in the D3-5 FET group. Although no statistically significant differences were observed in the number of transferred embryos and grade A embryos among the three groups, the pregnancy outcomes were significantly better in the D3-5 FET group, with higher biochemical, clinical pregnancy, implantation, and live-birth rates (all P

The discovery and characterization of the opaque endosperm gene provide ideas and resources for the production and application of maize. We found an o213 mutant whose phenotype was opaque and shrunken endosperm with semi-dwarf plant height. The protein, lipid, and starch contents in the o213 endosperm were significantly decreased, while the free amino acid content in the o213 endosperm significantly increased. The aspartic acid, asparagine, and lysine contents were raised in the o213 endosperm by 6.5-, 8.5-, and 1.7-fold, respectively. Genetic analysis showed that this o213 mutant is a recessive single-gene mutation. The position mapping indicated that o213 is located in a 468-kb region that contains 11 protein-encoding genes on the long arm of chromosome 5. The coding sequence analysis of candidate genes between the WT and o213 showed that ZmYSL2 had only a single-base substitution (A–G) in the fifth exon, which caused methionine substitution to valine. Sequence analysis and the allelic test showed that o213 is a new mutant allele of ZmYSL2. The qRT-PCR results indicated that o213 is highly expressed in the stalks and anthers. Subcellular localization studies showed that o213 is a membrane transporter. In the variation analysis of o213, the amplification of 65 inbred lines in GWAS showed that this 3-bp deletion of the first exon of o213 was found only in temperate inbred lines, implying that the gene was artificially affected in the selection process. Our results suggest that o213 is an important endosperm development gene and may serve as a genetic resource. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11032-022-01278-9.

The past few years have witnessed the great success of artificial metamaterials with effective medium parameters to control electromagnetic waves. Herein, we present a scheme to achieve broadband microwave low specular reflection with uniform backward scattering by using a coding metasurface, which is composed of a rational layout of subwavelength coding elements, via an optimization method. We propose coding elements with high transparency based on ultrathin doped silver, which are capable of generating large phase differences (∼180°) over a wide frequency range by designing geometric structures. The electromagnetic diffusion of the coding metasurface originates from the destructive interference of the reflected waves in various directions. Numerical simulations and experimental results demonstrate that low reflection is achieved from 12 to 18 GHz with a high angular insensitivity of up to ±40° for both transverse electric and transverse magnetic polarizations. Furthermore, the excellent visible transparency of the encoding metasurface is promising for various microwave and optical applications such as electronic surveillance, electromagnetic interference shielding, and radar cross-section reduction.

Simple and efficient catalytic routes have been explored to upgrade the raw lignin oil. Though homogeneous catalysis is easy to operate and possesses a high reaction rate, it also suffers from the ...

This paper proposes a spatial scanning method based on emission source microscopy (ESM), which extends the scanning point distribution from two-dimension (2D) plane to three-dimension (3D) volume space. A commonly used method is the planar scanning, which can determine the radiation source in the industrial field, but the increasing number of electronic devices, uneven shapes and other reasons make plane scanning difficult or require a higher price. Based on the characteristics of linear operation of ESM algorithm and Fourier transform, the three-dimensional scanning method obtained can better solve the shortcomings of planar 2D scanning. The simulation results show that under the same sampling point, the electric field data collected in three planes can also accurately locate the position of the radiation source.

Vaccine administration by subcutaneous or intramuscular injection is the most commonly prescribed route for inoculation, however, it is often associated with some deficiencies such as low compliance, high professionalism, and risk of infection. Therefore, the application of microneedles for vaccine delivery has gained widespread interests in the past few years due to its high compliance, minimal invasiveness, and convenience. This review focuses on recent advances in the development and application of microneedles for vaccination based on different delivery strategies, and introduces the current status of microneedle-mediated vaccination in clinical translation. The prospects for its application including opportunities and challenges are further discussed.

The yields of cereal crops grown on acidic soils are often reduced by aluminum (Al) toxicity because the prevalence of toxic Al3+ cations increases as pH falls below 5.0. The Al-dependent release of citrate from resistant lines of maize is controlled by ZmMATE1 which encodes a multidrug and toxic compound extrusion (MATE) transporter protein. ZmMATE6 is another member of this family in maize whose expression is also increased by Al treatment. We investigated the function of this gene in more detail to determine whether it also contributes to Al resistance. Quantitative RT-PCR measurements found that ZmMATE6 was expressed in the roots and leaves of Al-resistant and sensitive inbred lines. Treatment with Al induced ZmMATE6 expression in all tissues but several other divalent or trivalent cations tested had no effect on expression. This expression pattern and the induction by Al treatment was confirmed in ZmMATE6 promoter-β-glucuronidase fusion lines. Heterogeneous expression of ZmMATE6 displayed a greater Al-activated release of citrate from the roots and was significantly resistant to Al toxicity than controls. This was associated with reduced accumulation of Al in the root tissues. Our results demonstrated that ZmMATE6 expression is induced by Al and functions as a citrate transporter.

Here, deep sequencing results of the maize transcriptome in leaves and roots were compared under high-nitrogen (HN) and low-nitrogen (LN) conditions to identify differentially expressed circRNAs (DECs). Circular RNAs (circRNAs) are covalently closed non-coding RNA with widely regulatory potency that has been identified in animals and plants. However, the understanding of circRNAs involved in responsive nitrogen deficiency remains to be elucidated. A total of 24 and 22 DECs were obtained from the leaves and roots, respectively. Ten circRNAs were validated by divergent and convergent primers, and 6 DECs showed the same expression tendency validated by reverse transcriptase-quantitative PCR. Integrating the identified differentially expressed miRNAs, 34 circRNAs could act as miRNA decoys, which might play important roles in multiple biological processes, including organonitrogen compound biosynthesis and regulation of the metabolic process. A total of 51 circRNA-parent genes located in the genome-wide association study identified loci were assessed between HN and LN conditions and were associated with root growth and development. In summary, our results provide valuable information regarding further study of maize circRNAs under nitrogen deficiency and provide new insights into screening of candidate genes as well as the improvement of maize regarding nitrogen deficiency resistance. CircRNA-miRNA-mRNA co-expression networks were constructed to explore the circRNAs that participated in biological development and nitrogen metabolism.

Background: The yields of cereal crops grown on acidic soils are often reduced by aluminum (Al) toxicity because the prevalence of toxic Al3+cations increases as pH falls below 5.0. The Al-activated release from the roots of simple organic acids such as malate and citrate confers resistance to Al in a many plant species including maize (Zea mays L.). The Al-dependent release of citrate from resistant lines of maize is controlled by ZmMATE1 which encodes a multidrug and toxic compound extrusion (MATE) transporter protein. ZmMATE1 resides on chromosome 6 and its expression in roots is induced up to four-fold by Al treatment. ZmMATE6 is another member of this family in maize whose expression is also increased by Al treatment. We investigated the function of this gene in more detail to determine whether it also contributes to Al resistance. Results: Quantitative RT-PCR measurements found that in the absence of Al ZmMATE6 was expressed in the roots and leaves of Al-resistant and sensitive in-bred lines, and that expression levels in the root tips were lower than in the rest of the root tissue. Treatment with Al induced ZmMATE6 expression in all tissues but several other divalent or trivalent cations tested had no effect on expression. This expression pattern and the induction by Al treatment was confirmed in Arabidopsis lines transformed with β-glucuronidase where the ZmMATE6 promoter was used to drive expression. While subcellular localization of the ZmMATE6 protein could not be determined with confidence transgenic Arabidopsis lines expressing ZmMATE6 displayed a greater Al-activated release of citrate from the roots and were significantly more resistant to Al toxicity than controls. This was associated with reduced accumulation of Al in the root tissues. Conclusions: Our results demonstrated that ZmMATE6 expression is induced by Al and functions as a citrate transporter. While some findings are consistent with ZmMATE6 contributing to Al resistance in maize, further research is required to confirm this result.

Manufacturer-retailer relationships are often cited as an important determinant in product distribution. By coordinating the channel and aligning incentives, relationships can significantly affect both manufacturers’ and retailers’ profits and contribute to market concentration. However, empirical evidence is scarce because relationships are usually trade secrets. I study how beer manufacturers leverage their relationships with retailers to promote new products in the U.S. hard cider market. I present novel empirical evidence of mutual preferential treatments between manufacturers and retailers in assortment choices and wholesale pricing. I interpret the finding as pair-specific relationships sustained through repeated interactions, and use industry regulations on trade and wholesale pricing to address alternative mechanisms, including non-linear contracts. I estimate a structural model of consumer demand, retail and wholesale pricing, and assortment that incorporates the relationships. The results show that the relationships increase Anheuser-Busch InBev’s and MillerCoors’ new cider availability by 17.7% and 7.2%, respectively, and present a double win to both the manufacturers and retailers.

This study aimed to investigate the protective effects and underlying mechanism of seaweed polysaccharide (SWP) on intestinal epithelial barrier dysfunction induced by E. coli in an IPEC-J2 model. A preliminary study was done to screen optimum SWP concentrations by cell viability, cytotoxicity, apoptosis and proliferation evaluation. The regular study was conducted to evaluate the protective effects of SWP against E. coli challenge via the analysis of transepithelial electrical resistance (TEER), tight junction proteins, NF-κB signalling pathway, proinflammatory cytokines and the E. coli adhesion and invasion. Our results show that 4 h E. coli challenge down-regulated tight junction proteins expression, decreased TEER, activated NF-κB signalling pathway and increased proinflammatory response, which indicates that the E. coli infection model was well-established. Pre-treatment with 240 μg/ml SWP for 24 h alleviated the 4 h E. coli -induced intestinal epithelial barrier dysfunction, as evidenced by the up-regulated expression of Occludin, Claudin-1 and ZO-1 at both mRNA and protein level and the increased TEER of IPEC-J2 cells. Pre-incubation with 240 μg/ml SWP for 24 h inhibited the activation of the NF-κB signalling pathway by 4 h E. coli challenge, including the decreased mRNA expression of TLR-4, MyD88, IκBα, p-65, as well as the reduced ratio of protein expression of p-p65/p65. Also, pre-treatment with 240 μg/ml SWP for 24 h decreased proinflammatory response (IL-6 and TNF-α) induced by 4 h E. coli challenge and decreased the E. coli adhesion and invasion. In conclusion, SWP mitigated intestinal barrier dysfunction caused by E. coli through NF-κB pathway in IPEC-J2 cells and 240 μg/ml SWP exhibited better effect. Our results also provide a fundamental basis for SWP in reducing post-weaning diarrhoea of weaned piglets, especially under E. coli -infected or in-feed antibiotic-free conditions.

Background: Long noncoding RNAs (lncRNAs) play important roles in essential biological processes. However, our understanding of lncRNAs as competing endogenous RNAs (ceRNAs) and their responses to nitrogen stress is still limited.Results: Here, we surveyed the lncRNAs and miRNAs in maize inbred line P178 leaves and roots at the seedling stage under high-nitrogen and low-nitrogen conditions using lncRNA-Seq and small RNA-Seq. A total of 894 differentially expressed lncRNAs and 38 different miRNAs were identified. Co-expression analysis found two lncRNAs and four lncRNA-targets could competitively combine with ZmmiR159 and ZmmiR164, respectively. To dissect the genetic regulatory by which lncRNAs might enable adaptation to limited nitrogen availability. An association mapping panel containing a high-density single–nucleotide polymorphism (SNP) array (56,110 SNPs) combined with variable LN resistance-related phenotypes obtained from hydroponics was used for a genome-wide association study (GWAS). By combining GWAS and RNA-Seq, 170 differently expressed lncRNAs within the range of significant markers were screened. Moreover, 40 consistently LN-responsive genes including those involved in glutamine biosynthesis and nitrogen acquisition in root were identified. Transient expression assays in Nicotiana benthamiana demonstrated LNC_002923 could inhabit ZmmiR159-guided cleavage of Zm00001d015521. Conclusions: These lncRNAs containing trait-associated significant SNPs could consider to be related to root development and nutrient utilization. Taken together, the results of our study can provide new insights into the potential regulatory roles of lncRNAs in response to LN stress, and give valuable information for further screening of candidates as well as the improvement of maize regarding LN-responsive resistance.

Phosphorus deficiency is one of the major factors limiting plant growth and grain yield. Improving plant tolerance to Pi deficiency through genetic mechanism is an important source to increase grain yield. In this study, bioinformatics analysis, expression, and natural variation in ZmNAC134 gene with low Pi tolerant traits were analyzed under low Pi conditions. A total of 177 diverse heterotic groups of maize inbreds were used to identify the nucleotide diversity and alleles of ZmNAC134, which plays a vital role in the regulation of root architecture in response to Pi deficiency evolutionary results showed that ZmNAC134 has 3 homologous genes and these genes have one exon and conserved domain. The phenotypic traits showed significant difference for each of the 22 traits under deficient and sufficient Pi conditions. A total of 27 SNPs were identified in the coding region of ZmNAC134 and no InDels among 177 inbred lines. Among 27 SNPs, a total of 8 sites were highly significantly associated with multiple traits of low Pi tolerant trait index at − log10 P = 3.43. Although, 7 sites under Pi normal and 9 sites under Pi deficient conditions, of which four synonymous sites (position S24, S82, S164, and S1037) were associated with diverse number of traits in low Pi and normal Pi conditions and LD was not tight among these sites. Furthermore, the expression pattern was compared between Pi tolerant 178 and Pi sensitive 9782 inbred lines. ZmNAC134 was highly up-regulated in the roots and leaves of Pi tolerant 178 inbred line at 3 days, 7 days, and 9 days in roots and 7 days and 12 days in leaves while down-regulated in roots and leaves of Pi sensitive 9782 inbred line. In addition, protein encoded by ZmNAC134 was located in both nucleus and cytoplasm. Our findings provide the new insight of ZmNAC134 gene involved in low Pi stress and responsible against low Pi condition and the significant association of polymorphic loci with traits could be helpful to find out the molecular marker for genetic resources for further molecular maize breeding program.

SUMMARY Inorganic phosphorus (Pi) is an essential element in numerous metabolic reactions and signaling pathways, but the molecular details of these pathways remain largely unknown. In this study, metabolite profiles of maize (Zea mays L.) leaves and roots were compared between six low‐Pi‐sensitive lines and six low‐Pi‐tolerant lines under Pi‐sufficient and Pi‐deficient conditions to identify pathways and genes associated with the low‐Pi stress response. Results showed that under Pi deprivation the concentrations of nucleic acids, organic acids and sugars were increased, but that the concentrations of phosphorylated metabolites, certain amino acids, lipid metabolites and nitrogenous compounds were decreased. The levels of secondary metabolites involved in plant immune reactions, including benzoxazinoids and flavonoids, were significantly different in plants grown under Pi‐deficient conditions. Among them, the 11 most stable metabolites showed significant differences under low‐ and normal‐Pi conditions based on the coefficient of variation (CV). Isoleucine and alanine were the most stable metabolites for the identification of Pi‐sensitive and Pi‐resistant maize inbred lines. With the significant correlation between morphological traits and metabolites, five low‐Pi‐responding consensus genes associated with morphological traits and simultaneously involved in metabolic pathways were mined by combining metabolites profiles and genome‐wide association study (GWAS). The consensus genes induced by Pi deficiency in maize seedlings were also validated by reverse‐transcription quantitative polymerase chain reaction (RT‐qPCR). Moreover, these genes were further validated in a recombinant inbred line (RIL) population, in which the glucose‐6‐phosphate‐1‐epimerase encoding gene mediated yield and correlated traits to phosphorus availability. Together, our results provide a framework for understanding the metabolic processes underlying Pi‐deficient responses and give multiple insights into improving the efficiency of Pi use in maize., Significance statement Metabolite profiling and GWAS were applied to reveal maize low‐Pi response mechanisms.

Aluminum (Al) toxicity is one of the primary factors limiting crop production in acid soils worldwide. The cell wall is the major target of Al toxicity owing to the presence of many Al binding sites. Previous studies have found that XTH, encoding xyloglucan endohydrolase (XEH) and xyloglucan endotransglucosylase (XET), could participate in cell wall extension and affect the binding ability of the cell wall to Al by impeding the activities of these two enzymes. In this study, we found that ZmXTH, an XTH gene in maize, was involved in Al detoxification. The Al-induced up-regulation of ZmXTH occurred in the roots, prominently in the root tips. Additionally, the expression of ZmXTH was specifically induced by Al3+ but no other divalent or trivalent cations. Compared with the wild-type Arabidopsis, ZmXTH overexpressing plants grew more healthy and had decreased Al content in their root and root cell wall after Al stress. Overall, the results suggest that ZmXTH could confer the Al tolerance of transgenic Arabidopsis plants by reducing the Al accumulation in their roots and cell walls.

In this paper, a high-gain, low radar cross-section (RCS) and dual-frequency microstrip antenna is designed. The radome with a symmetrical two-layer frequency selective surface (FSS) is adopted to achieve the RCS reduction in a wide range of frequencies while maintaining the radiation characteristics. The FSS structure used in this work is a 5 × 5 array, composed of two layers of metal patches printed on both sides of the F4B substrate (e r = 2.65 and the thickness is 1.0mm). The associated simulation results show that the S parameter is less affected by the new antenna after loading the radome. The gain of the antenna is increased by 5.1 dB, which improves the radiation pattern of the antenna. At the same time, in the range of 2.0–18.0 GHz, the in-band and out-of-band RCS reduction of the antenna is more than 2.0 dB and the maximum reduction attains 15.0 dB.