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To investigate the beneficial effects of oridonin, a diterpenoid compound isolated from Rabdosia rubescens, on the inflammatory response in TNBS-induced post-inflammatory irritable bowel syndrome (PI-IBS) model and the underlying mechanism. Using the PI-IBS rat model and Caco-2 cell lines, we found that intestinal barrier function reflected by lactulose/mannitol (L/M) ratio and tight junction protein level was significantly ameliorated by oridonin. We also demonstrated that oridonin abrogated inflammation through inhibiting the phosphorylation of NF-κBp65 as well as its downstream gene (iNOS, COX-2, IL-1β, and IL-6) level. Molecular docking studies confirmed the good binding activity between oridonin and PXR. In Caco-2 cell lines, oridonin markedly inhibited LPS-induced NF-κB activation in a PXR-dependent manner. Meanwhile, PXR and its target genes CYP3A4 and P-gp were induced by oridonin, which was associated with the decreased expression of NF-κB and the recovery of intestinal barrier. This study indicated that the therapeutic effect of oridonin on experimental PI-IBS through repairing intestinal barrier function may be closely associated with the regulatory role of PXR/NF-κB signaling pathway. Oridonin may serve as a PXR ligand for the development of drugs in the therapy for PI-IBS.

A simple and sensitive liquid chromatography with tandem mass spectrometry method was developed for simultaneous quantification of paeoniflorin, albiflorin, oxypaeoniflorin, liquiritin, liquiritigenin, glycyrrhetinic acid, and glycyrrhizin in rat plasma after oral administration of Shaoyao-Gancao decoction, which is traditionally used in the treatment of polycystic ovary syndrome. The plasma samples were pretreated with methanol as precipitant. The method exhibited good linearity (correlation coefficient (R2 ) > 0.99) with lower quantification limits of 0.595-4.69 ng/mL for all analytes. Intra- and interbatch precision, accuracy, recovery, and stability of the method were all within accepted criteria. The results showed that the pharmacokinetic behaviors of the seven compounds were altered in the pathological status of polycystic ovary syndrome. Furthermore, a total of 36 metabolites were structurally identified based on their accurate masses and fragment ions. The major metabolic pathway involves phase I metabolic reactions (such as hydroxylation), phase II metabolic reactions (such as sulfation and glucuronidation conjugation) as well as the combined multiple-step metabolism. This study is the first report on the pharmacokinetic and metabolic information of Shaoyao-Gancao decoction in both normal and model rats, which would provide scientific evidences for the bioactive chemical basis of herbal medicines and also promote the clinical application of Shaoyao-Gancao decoction for treating polycystic ovary syndrome.

Postinflammatory irritable bowel syndrome (PI-IBS) is a common functional gastrointestinal disorder, which is characterized by abdominal pain, low-grade inflammation, and visceral hypersensitivity. Shaoyao-Gancao decoction (SGD) has been used to improve the clinical symptoms of abdominal spasmodic pain accompanying acute gastroenteritis, but the underlying therapeutic mechanism has not been fully elucidated. In the present study, a rat model of PI-IBS was established via rectal administration of TNBS. Rats were scored daily for 28 days using disease activity index (DAI). Abdominal withdrawal reflex (AWR) was used to measure the pain threshold. After SGD (6.25, 12.5, and 25 g/kg/d) treatment for 14 days, rat colonic tissue was collected for histopathological grading, enterochromaffin (EC) cell count, and 5-HT content measurement. RT-qPCR and western blot analyses were employed to detect the gene and protein level of tryptophan hydroxylase (TPH), serotonin reuptake transporter (SERT), and transient receptor potential vanilloid 1 (TRPV1). To further validate the effect of SGD on TRPV1, another experiment was performed in cells. The results revealed that visceral hyperalgesia, reflected by increased DAI, AWR, pathological injury score, 5-HT content, and EC cell count in PI-IBS rats, was significantly ameliorated by SGD. In cells, SGD markedly inhibited the expression and function of TRPV1. Moreover, the expression levels of TPH were also repressed by SGD. The findings of the present study indicated that the therapeutic effect of SGD on visceral hyperalgesia may be closely associated with the regulatory role of TRPV1 and 5-HT signaling pathways.

The lowest-energy structures and low-lying isomers of double impurity atoms, Ga and Mn, doped Li n (n = 1–12) clusters have been systematically investigated using density functional theory. The trimetallic clusters show larger relative binding energies compared with the bare Li n+2 partners, indicating doping with Ga and Mn atoms could enhance the stabilities of Li n clusters. The HOMO–LUMO gaps, the vertical ionization potentials and the vertical electron affinities have also been analyzed and compared with the pure lithium clusters. The magnetism calculations demonstrate that the magnetic moments of GaMnLi n clusters show a tunable magnetic properties with the increasing number of Li atoms.

Shaoyao-Gancao Decoction (SGD) has been widely used for the treatment of gynopathy. The present study aimed to evaluate the therapeutic effect and potential mechanism of SGD on hyperandrogenism in polycystic ovary syndrome (PCOS) rats. In the present work, SGD was orally administrated to the PCOS rats at the dose of 12.5, 25, and 50 g/kg/d for 14 consecutive days. UPLC–MS/MS was performed to identify the main chemical components of SGD. Body weight, ovarian weight, cystic dilating follicles, and serum levels of steroid hormones were tested to evaluate the therapeutic effect of SGD. In order to further clarify the underlying mechanism, we also measured mRNA and the protein levels of NF-κB, NF-κB p65, P-NF-κB p65, and IκB by RT-qPCR and Western blotting techniques. Our results showed that SGD treatment significantly alleviated hyperandrogenism in PCOS rats as evidenced by reduced serum levels of T and increased E2 and FSH levels. In addition, SGD effectively reduced the phosphorylation of NF-κB p65 and increased the expression of IκB. Results of the present study demonstrated that SGD could ameliorate hyperandrogenism in PCOS rats, and the potential mechanism may relate to the NF-κB pathway.

Near-infrared pigment is the key to control the near-infrared performance of solar heat-reflective coating which has good economic and application prospects as a new special coating. Green infrared reflective pigments were prepared through physical mixing, inorganic lake method and sol-gel processes in this study. Results show that the near-infrared spectral reflectance of composite pigments is improved when using inorganic lake method and sol-gel method. Chromaticity of composite pigment is the closest to phthalocyanine green when using sol-gel method. Physically mixing method is not suitable to prepare infrared reflective pigment. The coating materials have influence on the coating effect and the reflectivity of near-infrared spectral range in a certain extent.

In order to acquire a suitable ink for ink-jet printing technology, a graphene oxide ink was explored based on the GO aqueous dispersion. The GO dispersion was characterized by field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). The average particle diameter and zeta potential of the GO dispersion was determined by zeta potential & particle size analyzer. The GO ink is composed of 1,2-propanediol, diethylene glycol monobutyl ether, glycerol, polyvinyl pyrrolidone (PVP) and GO dispersion. The surface tension and viscosity of the GO ink was tested by surface tension meter and rheometer. The GO ink was inkjet printed on polyethylene terephthalate (PET) substrate. The optimal inkjet printing parameters were obtained and the printing quality was characterized by confocal laser scanning microscopy. The results show that the GO ink is suitable for inkjet printing technology and the morphology of the GO film with one printing pass has good uniformity.

The energetic and electronic properties of acetylenic-bond-interconnected hexagonal boron nitride sheets (BNyne), in which the number of rows of BN hexagonal rings (denoted as BN width) between neighboring arrays of acetylenic linkages increases consecutively, have been explored using first-principles calculations. Depending on the spatial position of B/N atoms with respect to the acetylenic linkages, there are two different types of configurations. The band structure features and band gap evolutions of BNyne structures as a function of the BN width can be categorized into two families, corresponding to two distinct types of configurations. In particular, for both types of BNyne structures, the band gap variations exhibit odd-even oscillating behavior depending on the BN width, which is related to the different symmetries of acetylenic chains in the unit cell. These results suggest that the embedded linear acetylenic chains can provide more flexibility for manipulation of the atomic and electronic properties of hexagonal boron nitride. These sp-sp(2) hybrid structures might promise importantly potential applications for developing nanoscale electronic and optoelectronic devices.

By using density functional theory (DFT) and MP2 method, we optimized the plane-form, chair-form, and boat-form of X3Y3H6 (X = B, Al, Ga, In Y = N, P, As, Sb) clusters. The results indicate that the plane form of X3N3H6 clusters are more stable than chair and boat form. For other considered clusters, the chair form is more stable than plane and boat form. The difference in energy between chair form and boat form are no more than 0.2 eV. B3N3H6 cluster is the most stable among considered clusters by calculating binding energy, and the stability of In3Sb3H6 cluster is the lowest. In addition, the binding energy of B3N3H6 cluster is 5.009 eV, and only 0.74 eV lower than that of C6H6(5.749 eV). By using AdNDP method, we found that B3N3H6 cluster has six π-electrons. According to Huckel’s 4n + 2 rule, it should be π aromatic, which also explains the stability of planar structure for B3N3H6 cluster. Other considered clusters are apt to chair form owing to pseudo–Jahn–Teller effect.

Taking Au38 as a prototype, hollow cages with different arrangements and those stuffed by a different number of atoms have been studied by using the scalar relativistic density functional theory. The global minimum structures of Au 38 (i = 0, ±1) are found to exhibit low symmetry core-shell structures: Au38 and Au 38 − feature a four-atom tetrahedral core and Au 38 + possesses a six-atom octahedron core. For the neutral Au38, the tube-like structure has the highest chemical stability. The obtained information forms the basis for future chemisorption studies to unravel the catalytic effects of gold nanoparticles.

First-principles calculations are carried out to investigate the hydrogen separation characteristics of two-dimensional carbon allotropes consisting of sp- and sp2-hybridized carbon atoms, i.e., graphyne, graphdiyne, and rhombic-graphyne. The selectivities for H2 over several gas molecules, including CO, N2, and CH4, are found to be sensitive to the pore sizes and shapes. The penetration barriers generally decrease exponentially with the pore sizes. Our results reveal that graphyne with small pores is unsuitable for the purpose of hydrogen separation. Graphdiyne, with larger pores, exhibits a high selectivity (109) for hydrogen over large gas molecules such as CH4, but a relatively low selectivity (103) over small molecules such as CO and N2. The large differences in diffusion barriers for molecules penetration through a rhombic-graphyne monolayer, which possesses pore size in between that of graphyne and graphdiyne, lead to a high selectivity (>1016) for hydrogen separation from the others. The results s...

In the frame of density functional theory, the lowest energy structures of Au 32− n Ag n ( n = 1–31) clusters are discussed by considering the hollow cage-like and space-filling structures. The calculated results show that the hollow cage-like and space-filling structures are competitive in energy. For Au 32− n Ag n clusters with sizes n = 1, 2, 5–8, 11, 12, 16, and 18, the hollow cage-like structures are their lowest energy structures. And for the clusters with other sizes, the space-filling structures are the corresponding lowest energy structures. In addition, the Au 31 Ag cluster with the hollow cage-like configuration is found to be highly stable in structure, and even more stable than the icosahedral Au 32 cluster. It believes that the experimentalists are interested in the finding above.

The equivalent continuous processing is done to multi-element composite foundation by composite material mechanics method, and the composite foundation is studied as transversely isotropic body, the constitutive relation of equivalent complex is established at first time. On the ABAQUS platform, the three direction seismic responses of multi-element composite foundation are studied by finite-infinite element coupling method. The results shown that: (1) the model of equivalent complex can reflect the working mechanics of the multi-element composite foundation; (2) with the increase of the total stiffness of the multi-element composite foundation, the max absolute values of horizontal accelerations and displacements decrease gradually. (3) With the increase of reinforced depth, the horizontal accelerations in reinforced area became small, but the displacements became big. The results can provide reference to the seismic design of structure.

The lowest-energy structures and low-lying isomers of Pbn (n = 13–18) clusters are obtained by using MP2 method. In the considered configuration and size range, it is found that the lowest-energy structures of Pbn clusters favor compact structures, which is different from the prolate structures of Snn clusters at the same size range. For the lowest-energy structures, our calculated dipole moments indicate that the Pb14 and Pb18 clusters possess large dipole moments, which are in good agreement with available experiment.

The geometries, stabilities, and electronic properties of Au n La (n = 2–8) clusters have been systematically investigated by using density-functional theory. The results show that the doped La atom prefers to locate at the center site with the number of Au atom increasing from 2 to 8. Furthermore, the Au n La clusters are more stable than the Au n+1 clusters. The charges transfer from La atom to Au atoms at n = 2–4, but charge-transferring is reversed at n = 5.

The geometries, electronic, and magnetic properties of the Au7Hn (n = 1–10) clusters have been systematically investigated by using relativistic all-electron density functional theory with generalized gradient approximation. It is found that the Au7 on the whole retains its triangle structure after hydrogen atoms adsorption and adsorbing hydrogen atoms can stabilize the Au7 structure. The Au7H7 cluster is much higher stability than the neighboring clusters. The pronounced even–odd alternation of the magnetic moments is observed in the Au7Hn systems indicating Au7Hn clusters possess tunable magnetic properties by adding even or odd number of H atoms.

The structural growth sequences and electronic properties of Au n ( n = 14 + 6 m and m = 0 , 1, 2, 3, 4, 5, 6, and 10) clusters have been investigated using the DMol 3 DFT package. The structures of Au n ( n = 20 , 26, 32, 38, 44, 50, and 74) are obtained in turn by directly adding a gold ring of six atoms on the tubelike configuration of Au 14 cluster. These tubelike gold clusters are all highly symmetric cages. Their average atomic coordination numbers, nearest-neighbor distances and average tube radius are very near. The average binding energies of Au n clusters increase substantially with size n. Au 14 , Au 26 , and Au 44 have larger energy gaps and ionization potentials than their neighboring clusters. During the studied clusters, Au 74 cluster has the highest average energy, ionization potential and the lowest electron affinity, which are corresponding to its highest structural and chemical stability, respectively.

The geometries, electronic, and magnetic properties of the 3d transition-metal-doped gold cluster: M@Au6 clusters (M = Sc, Ti, V, Cr, Mn, Fe, Co, Ni) have been systematically investigated by using ...

The geometric and electronic properties of the Au5Al cluster in its neutral and anionic charge states have been investigated using density-functional theory (DFT) at the PW91PW91 level. The nonplanar capped pyramid-type or headstand funnel structures are found to be the equilibrium geometric structures of Au5Al and Au5Al− clusters. Al atom prefers bonding in the center site of gold cluster. Also, the main features of the calculated molecular orbitals are well reproduced by one electron in Au5Al and Au5Al− clusters. NBO analysis indicates 6s orbital of Au atom hybridizes with 3s and 3p orbitals of Al atom in Au5Al cluster, and the electron changes from neutral to anionic cluster take place on all Au and Al atoms.

We have systematically studied the structural and electronic properties of LuSi n clusters with density functional theory. Especially, we employ an genetic algorithm (GA) global search to generate more than 300 configurations and to ensure that the lowest-energy structures of LuSi n clusters are reliable. We find that all the most stable structures of LuSi n clusters can be considered as a substitution of Lu atom for a Si atom in the lowest-energy structures of pure Si n + 1 clusters. The magic numbers of the different sized LuSi n clusters appear atn = 5, 8. The HOMO–LUMO gaps ( 1 eV for n = 1–12) suggest that Lu doping distinctly decreases the conduction band gap and increases metallic properties.

For the small rhenium boride clusters, we carried out detailed calculations based on density-functional theory. The results indicate that the ratio of boron to rhenium with 2:1 and 4:3 possess higher stability among considered Re m B n ( m = 1 – 3 , n = 1 – 3 m ) clusters, which the ratio with 2:1 was also found in the corresponding bulk phase. In addition, we also investigated the magnetic moment of Re m B n clusters. The results show that the magnetic moment of Re 2 B 6 cluster is as high as 4 μ B . Furthermore, the origin of the magnetic moment is analyzed and discussed.

The structures, stabilities and electronic properties of small-sized Ren (n ≤ 8) clusters have been systematically investigated by density-functional theory. The lowest-energy structures of Ren clusters favor 3-dimensional configuration. The results of second-order difference of energies indicate that Re4 and Re6 possess relatively higher stability in structure. Importantly, our theoretical results of electron affinity are in agreement with experimental values, which can be responsible for the reliability of the structures.

In the framework of density functional theory (DFT), the structure and magnetic properties of La-doped Sin clusters have been systematically studied. It is found that La atom always prefers locating on the surface site of the clusters and no cage-like structures are found up to n = 12. The La atom doping remarkably enhances the stabilities of silicon clusters. In contrast to some other clusters with the magnetic moment completely quenched, La doping is shown to invariable magnetism with the total spin magnetic moment of LaSin clusters 1 ¼B up to n = 24, as that of a free La atom.

The structures and stabilities of B n O and B n O2 clusters with n ≤ 6 are studied systematically by using density-functional theory. The lowest-energy structures of B n O clusters favor two-dimensional, and can be obtained from B n or B n−1O. For B n O2, unexpectedly, all of the most stable B n O2 clusters but B6O2 are linear. Furthermore, in B n O2 clusters, the longer the distance between two O atoms, the more stable the structure. To investigate the relative stability of considered clusters, binding energies per atom, reaction energies, and fragmentation energies are also calculated and discussed.

The structures, binding energies, and electronic properties of Cn and NaCn (n=2–12) clusters have been systematically investigated using density functional theory (DFT). A number of previously undiscovered isomers of NaCn clusters are reported, including fan-like, linear and three-dimensional structures. Moreover, NaCn clusters with even n are found to be more stable than those with odd n, in contrast with the case of Cn clusters.

New low-energy atomic structures and properties of medium-size gold nanoparticles (Au33-42) are studied, where the atomic positions of gold atoms are obtained on the basis of the generic formulation of shell and core concept. Hollow cage, tube-like, double-layered flat, fcc-like, and close-packed configurations are predicted. Relativistic density functional theory optimization indicated that low-symmetry stuffed configurations are all lower in energy than the others. Further analysis of the optimized structures of Au33-42 nanoparticles shows that these gold cores are all four-atom tetrahedral structures and similar to each other; only the number and positions of gold atoms at the surface of gold core are different. Compared with structure and electronic properties, Au33-42 nanoparticles have different structure stabilities and chemical activities. But they are all hybridizations of sp and d electrons. The obtained information forms the basis for future chemisorption studies to unravel the catalytic effects of gold nanoparticles.

We demonstrated a first-principles investigation to search for magnetic superatoms in the vanadium-doped lithium clusters VLi(n) (n = 1-13). The stabilities of VLi(n) clusters were determined through geometrical and electronic optimizations. It is found that the growth pattern of VLi(n) in 3-space follows adding a Li atom capped on VLi(n-1) clusters. All doped clusters show larger relative binding energies compared with pure Li(n+1) partners and display tunable magnetic properties. When n = 8-13, the VLi(n) clusters adopt a cage-like structure with an endohedral V atom and are identified as superatoms with their magnetic moments successively decreasing from 5 to 0 μB. The isolated VLi8 superatom is emphasized due to its robust magnetic moment as well as high structural and chemical stability analogue of a single Mn(2+) ion. Molecular orbitals analysis shows that VLi8 has an electronic configuration of 1S(2)1P(6)1D(5), exhibiting Hund's filling rule of maximizing the spin-like atoms. Electronic shell structures of 1S(2) and 1P(6) are virtually unchanged in Li9 cluster as the V atom substitutes for the embedded Li atom, indicating that the electron-shell-closing model is valid for explaining its structures and stabilities. The results show that the tailored magnetic building blocks for nanomaterials can be formed by seeding magnetic dopants into alkali metal cluster cages.

The geometries and electronic properties of gold clusters doped with atoms containing 3p valence electrons (MAu n ; M = Al, Si, P, S, Cl; n = 2−8) have been systematically investigated using density functional theory (DFT) at the PBE/LANL2DZ level. A number of low-energy isomers are identified for neutral MAu n clusters. It is found that doping with different 3p impurity atoms can drastically influence the geometrical structures, relative stabilities, electronic properties, and growth-pattern behaviors of gold clusters, which is very different from the case of 3d transition-metal impurity doped Au n clusters. Partially filled 3p electron impurities can stabilize Au clusters. In particular, SiAu4 cluster with T d symmetry have been found to have highly stable geometries and electronic structures with binding energies of 2.43 eV per atom (0.96 eV higher than pristine Au5 clusters), large HOMO-LUMO gaps (2.17 eV), and vertical ionization potentials of 8.68 eV. Using scalar relativistic molecular dynamics at T = 300 K, we show that the T d symmetry structure of SiAu4 is stable. The frontier molecular orbitals (HOMO and LUMO) and the partial densities of states (PDOS) show that strong hybridization occurs between the atomic orbitals of Si and Au atoms, resulting in strong Si-Au bonding. In addition, the vertical ionization potential, the vertical electron affinity, and charge transfers of MAu n clusters have also been analyzed. Our results are in good agreement with available experimental data.

The geometries, stabilities, and electronic properties of Bn and AlBn clusters, up to n=12, have been systematically investigated by using the density-functional approach. The results of Bn clusters are in good agreement with previous conclusions. When the Al atom is doped in Bn clusters, the lowest-energy structures of the AlBn clusters favor two-dimensional and can be obtained by adding one Al atom on the peripheral site of the stable Bn when nor=5. Starting from n=6, the lowest-energy structures of AlBn clusters favor three-dimensional and can be described as an Al atom being capped on the Bn clusters. The average atomic binding energies, fragmentation energies, and second-order energy differences are calculated and discussed. Maximum peaks were observed for clusters of sizes n=5, 8, 11, especially for the AlB8 cluster, implying that these clusters possess relatively higher stability. The adiabatic IP and EA of AlBn and Bn clusters are discussed and compared with some available experimental results. A distinct phenomena for AlBn clusters is that all even n, but n=10, have higher adiabatic ionization potentials than odd n.

Discovering highly stable metal fullerenes such as the celebrated C60 is interesting in cluster science as they have potential applications as building blocks in new nanostructures. We here investigated the structural and electronic properties of the fullerenes M12@Au20 (M = Na, Al, Ag, Sc, Y, La, Lu, and Au), using a first-principles investigation with the density functional theory. It is found that these compound clusters possess a similar cage structure to the icosahedral Au32 fullerene. La12@Au20 is found to be particularly stable among these clusters. The binding energy of La12@Au20 is 3.43 eV per atom, 1.05 eV larger than that in Au32. The highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) gap of La12@Au20 is only 0.31 eV, suggesting that it should be relatively chemically reactive.