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Graphical abstract Terpenoids are natural compounds predominantly present in plants. They have many pharmaceutical and/or nutritional functions, and have been widely applied in medical, food, and cosmetics industries. Recently, terpenoids have been used in the clinical treatment of COVID-19 due to the good antiviral activities. The increasing demand for terpenoids in international markets poses a serious threat to many plant species. For environmentally sustainable development, microbial cell factories have been utilized as the promising platform to produce terpenoids. Nevertheless, the bioproduction of most terpenoids cannot meet commercial requirements due to the low cost-benefit ratio until now. The biosynthetic potential of endophytes has gained attention in recent decades owing to the continual discovery of endophytes capable of synthesizing plant bioactive compounds. Accordingly, endophytes could be alternative sources of terpenoid-producing strains or terpenoid synthetic genes. In this review, we summarized the research progress describing the main and supporting roles of endophytes in terpenoid biosynthesis and biotransformation, and discussed the current problems and challenges which may prevent the further exploitation. This review will improve our understanding of endophyte resources for terpenoid production in industry in the future. The four main research interests on endophytes for terpenoid production. A: Isolation of terpenoid-producing endophytes; B: The heterologous expression of endophyte-derived terpenoid synthetic genes; C: Endophytes promoting their hosts’ terpenoid production. The blue dashed arrows indicate signal transduction; D: Biotransformation of terpenoids by endophytes or their enzymes. Key points • The mechanisms employed by endophytes in terpenoid synthesis in vivo and in vitro. • Endophytes have the commercial potentials in terpenoid bioproduction and biotransformation. • Synthetic biology and multiomics will improve terpenoid bioproduction in engineered cell factories.

To test the hypothesis that stay-green genotypes help to increase stalk lodging resistance under high planting density by reducing dry matter remobilization from stalk, a two-year field study with three planting densities (60,000, 75,000, and 90,000 plants per ha) and six hybrids was conducted. When planting density changed from 75,000 to 90,000, stalk dry matter remobilization efficiency increased by 4.1–191%. Stem dry weight per length, rind penetration strength, average crushing strength for the first to fifth internode, and average bending strength for the third to fifth internode decreased by 25.4–47.2%, 5.1–24.6%, 1.4–29.9%, and 14.0–36.0%, respectively. Stalk lodging rate increased by 17–275%. Stalk dry matter remobilization efficiency was negatively correlated to either stem dry weight per length (r = 0.23, p

Knowledge of accurate values of elastic modulus of (Al1– x Sc x )N is required for design of piezoelectric resonators and related devices. Thin films of (Al1– x Sc x )N across the entire composition space are deposited and characterized. Accuracy of modulus measurements is improved and quantified by removing the influence of substrate effects and by direct comparison of experimental results with density functional theory calculations. The 5%–30% Sc compositional range is of particular interest for piezoelectric applications and is covered at higher compositional resolution here than in previous work. The reduced elastic modulus is found to decrease by as much as 40% with increasing Sc concentration in the wurtzite phase according to both experimental and computational techniques, whereas Sc-rich rocksalt-structured films exhibit little variation in modulus with composition.

To test the hypothesis that plants could remobilize more nutrients from vegetative organs to fulfill the requirement of grain formation under high planting density, eight maize cultivars with different leaf senescence characters were chosen to study the relationship between stay-green character, nutrient (N, P, K) accumulation, post-silking nutrient remobilization and grain yield under three planting densities (60,000, 75,000, and 90,000 plants per ha) in 2 years. We found that increased plant density aggravated leaf senescence, reduced concentration of N, P and K in all organs, reduced post-silking N, P, K accumulation per ha, increased nutrient remobilized efficiency. Stay-green degree was positively correlated to yield reduction at high planting density (R2 = 0.35, P 2 = 0.29, P 2 = 0.51, P 2 = 0.17, P

Zr and Y co-doped perovskite BaCo0.4Fe0.4Zr0.1Y0.1O3−δ (BCFZY0.1) was recently developed as a promising new cathode for protonic ceramic fuel cells (PCFCs). Here, it is applied for the first time as a cathode for low-temperature solid oxide fuel cells (LT-SOFCs). It exhibits large lattice parameters, high oxygen reduction reaction (ORR) activity, exceptional low-temperature performance, long-term stability, and excellent chemical compatability with ceria-based SOFC electrolytes. When BCFZY0.1 is used as the cathode in Ce0.8Gd0.2O2−δ (GDC20)-based SOFCs, it enables a peak power density of 0.97 W cm−2 at 500 °C with 2500 hours stable performance and complete recoverability without any degradation after more than 80 fast thermal ramping cycles. Even at 350 °C, peak power density reaches 0.13 W cm−2. It also shows good H2O and CO2 tolerance.

Certain alumino-silicates display exotic properties enabled by their framework structure made of corner-sharing tetrahedral rigid units. Using in situ diamond-anvil cell x-ray diffraction (XRD), we study the pressure-induced transformation of β eucryptite, a prototypical alumino-silicate that undergoes a phase transformation at moderate pressures. The atomic structure and symmetry group of the new pressure-stabilized phase has not yet been reported. Based on density functional theory studies and Rietveld analysis of XRD patterns, we find that the new phase belongs to the Pna2 1 space group and report its atomic structure. Furthermore, we discover two other possible pressure-stabilized polymorphs, P1c1 and Pca2 1.

Knowledge of accurate values of elastic modulus of (Al

While it is well established that ionic conduction in lithium aluminosilicates proceeds via hopping of Li ions, the nature of the various hoping-based mechanisms in different temperature regimes has not been fully elucidated. The difficulties associated with investigating the conduction have to do with the presence of grains and grain boundaries of different orientations in these usually polycrystalline materials. Herein, we use electrochemical impedance spectroscopy (EIS) to investigate the ion conduction mechanisms in -eucryptite, which is a prototypical lithium aluminosilicate. In the absence of significant structural transitions in grain boundaries, we have found that there are three conduction regimes for the one-dimensional ionic motion along the c axis channels in the grains, and determined the activation energies for each of these temperature regimes. Activation energies computed from molecular statics calculations of the potential energy landscape encountered by Li ions suggest that at temperatures below 440 {\deg}C conduction proceeds via cooperative or correlated motion, in agreement with established literature. Between 440 {\deg}C and 500{\deg}C, the activation barriers extracted from EIS measurements are large and consistent with those from atomistic calculations for uncorrelated Li ion hopping. Above 500 {\deg}C the activation barriers decrease significantly, which indicates that after the transition to the Li-disordered phase of -eucryptite, the Li ion motion largely regains the correlated character., Comment: submitted to Journal of American Ceramic Society