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A polysaccharide (ALP-1) extracted from Atractylodes lancea (Thunb.) DC. was carboxymethylated (C-ALP-1), phosphorylated (P-ALP-1) and acetylated (A-ALP-1) to improve its physicochemical properties and bioactivities. The solubility of all derivatives was increased, and the solubility of A-ALP-1 increased to 137.5 mg/mL, which was much higher than the solubility of ALP-1 (15.0 mg/mL). The results of HPSEC-MALLS-RID showed that the molecular weight of polysaccharides was slightly increased after the modification, and the root mean square radius of rotation (Rz) and morphology of polysaccharides in solution were also changed. The scanning electron microscopy (SEM) and X-ray diffraction (XRD) results confirmed that the surface morphology of ALP-1 changed dramatically and the crystallinity decreased after structural modification. From thermal analysis results, the T

The highbush blueberry (Vaccinium corymbosum) Duke, was used to construct a de novo transcriptome sequence library and to perform data statistical analysis. Mega 4, CLC Sequence Viewer 6 software, and quantitative PCR were employed for bioinformatics and expression analyses of the basic helix-loop-helix (BHLH) transcription factors of the sequencing library. The results showed that 28.38 gigabytes of valid data were obtained from transcriptome sequencing and were assembled into 108 033 unigenes. Functional annotation showed that 32 244 unigenes were annotated into Clusters of Orthologous Groups (COG) and Gene Ontology (GO) databases, whereas the rest of the 75 789 unigenes had no matching information. By using COG and GO classification tools, sequences with annotation information were divided into 25 and 52 categories, respectively, which involved transport and metabolism, transcriptional regulation, and signal transduction. Analysis of the transcriptome library identified a total of 59 BHLH genes. Sequence analysis revealed that 55 genes of that contained a complete BHLH domain. Furthermore, phylogenetic analysis showed that BHLH genes of blueberry (Duke) could be divided into 13 sub-groups. PCR results showed that 45 genes were expressed at various developmental stages of buds, stems, leaves, flowers, and fruits, suggesting that the function of BHLH was associated with the development of different tissues and organs of blueberry, Duke. The present study would provided a foundation for further investigations on the classification and functions of the blueberry BHLH family.

Order reconstruction in an inverse twisted nematic (ITN) liquid crystal cell with an applied electric field is investigated based on Landau–de Gennes theory and the two-dimensional finite-difference iterative method. Twice eigenvalue exchange in three-axis layer configuration, thrice eigenvalue exchange in four-axis layer configuration, and negative order parameter uniaxial twisted state exist in this cell, which can be described by the order parameter tensor Q in equilibrium state. The twice eigenvalue exchange also has two degenerate configurations with reduced electric field E from 0.8 to 2.8 in 10ξ cell (ξ is the biaxial correlation length). Moreover, two critical cell gaps d c ⁎ ⁎ = 7 ξ and d c ⁎ = 12 ξ are included in the study of the ITN cell. When d ≤ d c ⁎ ⁎ , only the eigenvalue change state exists. When d ≥ d c ⁎ , only a positive order parameter uniaxial twisted state exists near the threshold electric field. When d c ⁎ ⁎ d d c ⁎ , a negative order parameter uniaxial twisted state exists near the threshold electric field. Comparison of the eigenvalue exchange solutions of different cell gaps of 5ξ, 10ξ, and 20ξ shows that smaller cell gap can inhibit the complexity of the eigenvalue exchange solution and reduce the number of axis layers. This research provides a theoretical basis for the change of multi-axis layer defect and promotes the concept of eigenvalue exchange.

The research on gyroscopes has lasted for a long time, but there is not a thorough analysis of them. In this paper, a detailed theoretical analysis of fiber ring gyroscope and its gyroscope effect are presented, the performance characteristics of optical resonator gyroscope ranging from transmission function Tfrr, Finesse, Q -factor, the gyro sensitivity, signal noise ratio, random walk to dynamic range are all deduced in detail. In addition, a large number of experiments have been done to verify the deduced theoretical results. The sensitivity of the fiber optic gyroscope is analyzed by simulating the relationship between dQ and turn number of fiber ring, make the conclusion that with the increase of turn number of ring, the resonance depth increased while the dQ value decreased, obtain a high sensitivity of 0.21°/h, random walk of 0.0035°/√h, and Q factor of 8 × 10 6 . Moreover, in the digital frequency locked dual rotation gyro experiments, obvious step effect is observed. And the experimental line of frequency difference is very agreement with the theoretical line. The research provides a good theoretical and experimental basis for the study of gyroscopes.

The biotransformation of huperzine A (hupA), one of the characteristic bioactive constituents of the medicinal plant Huperzia serrata, by a fungal endophyte of the host plant was studied. Two previously undescribed compounds 1–2, along with a known analog 8α,15α-epoxyhuperzine A (3), were isolated and identified. The structures of all the isolates were established by spectroscopic methods including NMR, MS, IR, and UV spectra. In particular, the absolute configurations of 1 and 2 were elucidated by CD spectra comparison and theoretic NOE strength calculation. In the LPS-induced neuro-inflammation injury assay, 1–3 exhibited moderate neuroprotective activity by increasing the viability of U251 cell lines with EC50 values of 35.3 ± 0.9, 32.1 ± 0.9, and 50.3 ± 0.8 nM, respectively.

A nematic liquid crystal slab composed of N molecular layers is investigated using a simple cubic lattice model, based upon the molecular pair potential which is spatially anisotropic and dependent on elastic constants of liquid crystals. A perfect nematic order is assumed in the theoretical treatment, which means the orientation of the molecular long axis coincides with the director of liquid crystal and the total free energy equals to the total interaction energy. We present a modified Gruhn–Hess model, which is relative to the splay-bend elastic constant K 13 . Furthermore, we have studied the free nematic interfacial behavior (intrinsic anchoring) by this model in the assumption of the perfect nematic order. We find that the preferred orientation at the free interface and the intrinsic anchoring strength change with the value of modification, and that the director profile can be determined by the competition of the intrinsic anchoring with external forces present in the system. Also we simulate the intrinsic anchoring at different temperatures using Monte Carlo method and the simulation results show that the intrinsic anchoring favors planar alignment and the free interface is more disordered than the bulk.

A solid-phase copolymer of 4-vinylpyridine is shown to be a highly effective reagent/ catalyst for the synthesis of acid anhydrides from mixtures containing equimolar quantities of carboxylic acids and acid chlorides. The process may be carried out in batch or column mode.

Symmetrical anhydrides are produced quickly and in high yield by treating mixtures of a carboxylic acid and one-half equivalent thionyl chloride in dichloromethane with a solid-state copolymer of 4-vinylpyridine. This conversion is accomplished equally well in batch or column mode.