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Hawk tea, prepared from the young leaves of Litsea coreana Levl. var. lanuginosa, is consumed as a tonic in China. Essential oils (EOs) from Hawk tea collected from six habitats in China were obtained by hydro distillation. Extraction yields ranged from 0.42% (g/g) in samples from Ningguo to 0.11% (g/g) in samples from Qingchuan. A total of 50 compounds in the six EO samples were identified by Gas Chromatography-Mass Spectrometer. The dominant compounds were citral (4.67–21.12%), caryophyllene (2.31–15.74%), dodecanal (2.10–15.38%), α-humulene (1.45–13.56%) and decanal (1.91–13.17%). Altitude may contribute the greatest effect on the chemical variation of the six EO samples. All the EO samples showed bioactivities. Among them, the EOs from the Pingshan sample showed the best ABTS radical scavenging activity (78.67 mg TEs /g) and better antimicrobial activities (MIC = 156.25–625 μg/mL) and had stronger DPPH radical scavenging activity (IC50 = 0.71 mg/mL) than BHT (IC50 = 0.76 mg/mL). The EOs from the Ningguo sample showed the highest reducing power (26.06 mg Fe2+/g) in a FRAP assay, the best inhibitory effect on α-glucosidase (1.71 mg/mL) and was the most cytotoxic (66.03–77.03 μg/mL) in an MTS assay. Therefore, the EOs from Hawk tea could be suitable for commercialization in the food, cosmetic or medical industries. Due to the activities of their EOs, plants growing in Pingshan and Ningguo are the optimal candidates.

Transition metal oxides (TMOs) generally suffer severe capacity degradation as the potential anode materials for lithium-ion batteries, since the large volume changes of TMO anodes during conversion reactions result in the collapse of electrode structures. Fabricating specific nanostructures of TMOs has been demonstrated as a successful approach to partially solve this issue. Besides the concern of capacity retention, our previous work has demonstrated that the specific capacities of TMOs can be improved by enhancing their degrees of crystallinity. Therefore, the TMO nanostructures with high degrees of crystallinity are highly desired to achieve both high specific capacity and good capacity retention. However, the high crystallinity and desired nanostructure are usually contradictory in nanofabrication since the thermal treatment will lead to the collapse of a nanostructure. To overcome the obstacle, herein, the polydopamine coating followed by a thermal treatment in nitrogen is first introduced as a confined crystallization strategy to enhance the degree of crystallinity and simultaneously maintain the nanostructure of ZnO microspheres. Electrochemical performance tests demonstrate that the appropriate coating thickness and heat treatment can enhance the specific capacity from 288.0 mAh g−1 of pristine ZnO to 527.0 mAh g−1 of carbon coated ZnO after 100 cycles. The present work provides a good opportunity to develop TMO anodes with high capacities and superior cycling performances by the polydopamine-derived carbon coating and confined crystallization.

The incorporation of organic fluorescent dyes into inorganic matrixes could greatly improve the luminous properties of organic dyes. In this study, we investigated the effect of three different types of layered mineral clays on the luminous properties of lucigenin (bis-N-methylacridinium nitrate, BNMA). Attempts were made to fit the isothermal data using Langmuir and Freundlich equations. The adsorption of BNMA onto montmorillonite and kaolinite were fitted well by Langmuir isotherm equation while that of BNMA onto rectorite was fitted by Freundlich equation. The results indicated that the adsorptive behavior, which was resulted from the different layer structures, had a direct impact on the luminous properties of the composites.

Having virtual continuous axes is an important mechanism performance required by the motion tracking and simulating mechanisms for large-scale heavy-weight apparatus. Mathematical criteria for a virtual continuous axis using virtual coefficient theory is proposed through geometric modeling continuous rotation of the constrained rigid body and a virtual continuous axis. A type of synthesis approach for rotational parallel mechanisms (RPMs) with a virtual continuous axis is given and a type of RPM with arc-rail-slider or cross slipper is constructed. On the basis of screw theory, degree of freedom (DoF) and properties of the axes of a typical RPM with a virtual continuous axis are analyzed, and the inputs selection and arrangement are also discussed. The kinematic and dynamic models of the RPM are established. Finally, a numerical example and a solution to the motion simulation for super-large-scale heavy-weight apparatus are given.

Summary The lymphatic vasculature plays important roles in the physiology of the organs in which it resides, though a clear mechanistic understanding of how this crosstalk is mediated is lacking. Here, we performed single-cell transcriptional profiling of human and mouse adipose tissue and found that lymphatic endothelial cells highly express neurotensin (NTS/Nts). Nts expression is reduced by cold and norepinephrine in an α-adrenergic-dependent manner, suggesting a role in adipose thermogenesis. Indeed, NTS treatment of brown adipose tissue explants reduced expression of thermogenic genes. Furthermore, adenoviral-mediated overexpression and knockdown or knockout of NTS in vivo reduced and enhanced cold tolerance, respectively, an effect that is mediated by NTSR2 and ERK signaling. Inhibition of NTSR2 promoted energy expenditure and improved metabolic function in obese mice. These data establish a link between adipose tissue lymphatics and adipocytes with potential therapeutic implications.

A mechanism not only bears loads on the output but also endures loads from gravity, inertia, and other types of stresses from the environment on all rigid bodies (or links). These loads are collectively called external wrenches. Internal wrenches, which include the constraint loads of joints and the driving loads of actuators, resist external wrenches. Mapping from internal to external wrenches can provide an extensive evaluation of the mechanism considering all the constraint loads of the joints, the driving loads of the actuators, and all the possible loads of each rigid body. This paper proposes a novel index that can evaluate a mechanism by considering both the internal and external wrenches. First, the whole wrench mapping matrix from the internal to the external wrenches is built based on the digraph connections of the rigid bodies. Second, with the condition number of the matrix, the whole wrench index is obtained to evaluate the mapping from internal to external wrenches, and its physical interpretation is studied. Finally, two kinds of parallel mechanisms are analyzed to indicate the significance and universality of the novel index.

Human health safety and environmental concerns have resulted in the widespread deregistration of several agronomic important nematicides. New and safer nematicides are urgently needed. However, a high-throughput bioassay for screening potential nematicides has not been established. We developed a two-step high-throughput nematicidal screening method to combine a cell-based MTS colorimetric assay with Caenorhabditis elegans embryo cells for preliminary cytotoxicity screening (step 1) followed by in vitro larval assay for nematicidal activity (step 2). Based on three conventional nematicides' test, high correlations were obtained between cell viability and larval viability and "r" values were 0.78 for Avermectin, 0.95 for Fosthiazate, and 0.65 for Formaldehyde solution. Further assays with 60 fungal secondary metabolites (extracts, fractions and pure compounds) also demonstrated the high correlation between cell viability and larval viability (r=0.60) and between the C. elegans cell viability and the juvenile viability of soybean cyst nematode Heterodera glycines (r=0.48) and pine wood nematode Bursaphelenchus xylophilus (r=0.56). Six metabolites with high cytotoxicity have performed high larval mortality with a LC50 range of 6.8-500μg/ml. These results indicate that the proposed two-step screening assay represents an efficient and labor-saving method for screening natural nematicidal products.

Previous study demonstrated large scale production of trichochecenes which limited the discovery of novel metabolites in Trichoderma hypoxylon. By genetic deletion of trichothecene synthase encoding gene thtri5, we created the dereplication mutant which eliminated the production of trichothecenes. Through chemical isolation, we characterized a couple of rare new polycyclic lactones tricholactones A and B from the thtri5 deletion strain. The structures of these two compounds were well determined by NMR, HR-ESI-MS and IECD analysis.