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As a classic prescription and commercial Chinese patent medicine, Zuojin Pill (ZJP) has been used to treat ulcerative colitis (UC) effectively for many years. However, its mechanism of action remains unclear. Aim of the study: Mice with dextran-sulfate-sodium-induced colitis were treated with ZJP for 7 d. In the present study, the therapeutic effect of ZJP was evaluated by macroscopic and microscopic observation; regulatory T (Treg) cells and their subsets were analyzed by flow cytometry; and the composition of gut microbiota was tested by 16S rRNA analysis. Activation of the phosphoinostide 3-kinase (PI3K)/Akt signaling pathway was observed by western blotting. The pathological damage was attenuated and expression of proinflammatory cytokines was decreased. While the diversity of intestinal microflora was regulated, the relative abundance of Actinobacteria , and Sphingobacteriia was modified. Meanwhile, the level of CD4+CD25+Foxp3+ and PD-L1+ Treg cells improved. These changes maintained a positive correlation which was analyzed statistically. Our results also showed that ZJP inhibited activation of the PI3K/Akt signaling pathway. ZJP regulates crosstalk between intestinal microflora and Treg cells to attenuate experimental colitis via the PI3K/Akt signaling pathway. Image 1 [ABSTRACT FROM AUTHOR]

The lack of the vertical piezoelectricity and the corresponding internal physical mechanism of diamanes limit their applications in the piezoelectric field. The vertical piezoelectricity of the diamane doped with Si/Ge atoms is studied systematically by the first principles calculation. These monolayer diamanes can be regarded as the vertical piezoelectric nano-switches with a moderate barrier. Based on the 25 kinds of monolayers' data, the super-dipole-moment effect is found as the internal mechanism of larger vertical piezoelectricity based on the ordered phase of Born effective charges. It may deepen the understanding of the internal physical mechanism about the piezoelectricity. [ABSTRACT FROM AUTHOR]

Recently, two-dimensional (2D) piezoelectric materials are widely studied, and the vertical piezoelectric properties of 2D materials are highly required to be known in the related theory research works and experiments, so it becomes very important to explore the intrinsic mechanism of piezoelectricity in the 2D materials. Herein, we systematically study the piezoelectricity of Janus C3HFX (X = Si and Ge) monolayers with semiconductor property, which are carbon-based 2D materials, using the first-principles calculation. The remarkable enhancements on the absolute values of the vertical piezoelectric coefficient of C3HFSi-1 (e33 = 11.27 × 10−10 C/m) and C3HFGe-4 (e33 = −12.78 × 10−10 C/m) are larger than that of C4HF (e33 = −2.28 × 10−10 C/m) by 5 and 6 times, respectively. It indicates that the atom replacement at appropriate positions in the multiatomic monolayer can significantly enhance the vertical piezoelectric properties based on the appropriate distribution of polarization charge. We define the concepts, the Born effective charges center (BECs-center) and the BECs-dipole-moment in this work, to explain these large vertical piezoelectric coefficients' variation. The larger BECs-dipole-moment will enhance the vertical piezoelectricity for these C3HFX monolayers than that of the C4HF monolayer. These concepts defined in this work will deepen the understanding of the internal physical mechanism about the piezoelectricity. [ABSTRACT FROM AUTHOR]

The above-threshold ionization process of ammonia molecules induced by a femtosecond laser field at 800 nm is studied in the intensity range from 1.6 Ă— 1013 to 5.7 Ă— 1013 W/cm2. Channel switching under different laser intensities is observed and identified in the photoelectron kinetic energy spectra of ammonia. Based on the photoelectron kinetic energy distributions and the photoelectron angular distributions, the characteristic peaks observed are exclusively assigned to the multiphoton resonance through certain intermediate states, followed by multiphoton above-threshold ionization. [ABSTRACT FROM AUTHOR]

We investigate the molecule dissociation and separation roles of graphene membranes with different functionalized monovacancies using first-principles density functional theory calculations. We have found that the boron-functionalized graphene vacancy can effectively dissociate one H2 molecular into two hydrogen atoms through a novel nano-pulling effect; at the same time it can separate the two hydrogen atoms on different sides of the graphene monolayer, with about 0.21 eV net adsorption energy. The boron-functionalized monovacancy acts like a pair of nanoscissors in this process. The binding energies of the two separated hydrogen atoms with the boron-functionalized monovacancy are 2.82 eV and 1.54 eV, respectively, in the two releasing steps. The boron-functionalized graphene monovacancy as a molecular dissociator can remarkably decrease the potential barrier of H2 dissociation compared to that of 4.58 eV for free H2 molecules. This method may open up new avenues for the development of safe hydrogen storage and biomimic photosynthesizers. [ABSTRACT FROM AUTHOR]

The ionization processes of NH3 molecule are studied by photoelectron velocity map imaging technique in a linearly polarized 400-nm femtosecond laser field. The two-dimensional photoelectron images from ammonia molecules under different laser intensities are obtained. In the slow electron region, the values of kinetic energy of photoelectrons corresponding to peaks 1, 2, 3, and 4 are 0.27, 0.86, 1.16, and 1.6 eV, respectively. With both the kinetic energy and angular distribution of photoelectrons from NH3 molecules, we can confirm that the two-photon excited intermediate Rydberg state is A∼1 () state for photoelectron peaks 2, 3, 4, and the three peaks are marked as 1223 (2 + 2), 1123 (2 + 2), and 1023 (2 + 2) multi-photon processes, respectively. Then, peak 1 is found by adding a hexapole between the source chamber and the detection chamber to realize the rotational state selection and beam focusing. Peak 1 is labeled as the 1323 (3 + 1) multi-photon process through the intermediate Rydberg state. The phenomena of channel switching are found in the slow electron kinetic energy distributions. Our calculations and experimental results indicate that the stretching vibrational mode of ammonia molecules varies with channels, while the umbrella vibration does not. In addition, we consider and discuss the ac-Stark effect in a strong laser field. Peaks 5 and 6 are marked as (2 + 2 + 1) and (2 + 2 + 2) above threshold ionization processes in the fast electron region. [ABSTRACT FROM AUTHOR]

Highlights • The SnN-InO is more flexible than graphene. • The SnN-InO has the remarkable out-of-plane piezoelectric coefficient d 31. • The SnN-InO can be applied in naonscale energy harvesting devices and nano-sensor. Abstract Piezoelectricity can realize the mutual conversion between mechanical energy and electrical energy. With the development of science and technology, the biggest challenge now is to look for the materials with higher efficiency piezoelectric effect. Using first-principles calculations, we study the elastic and piezoelectric properties of the V-IV-III-VI sheets: SiN-AlO, GeN-GaO, and SnN-InO. The Young moduli of these three V-IV-III-VI sheets are much smaller than graphene. Among these three V-IV-III-VI sheets, the in-plane piezoelectric coefficient d 11 (12.69 pm/V) of SnN-InO is the largest, which is larger than that (3.73 pm/V) of molybdenum disulfide (MoS 2) by 3 times. SnN-InO also exhibits the largest out-of-plane piezoelectric coefficient d 31 (8.66 pm/V), which is larger than that (0.46 pm/V) of the Janus group-III chalcogenide sheets by 18 times. The broken inversion symmetry and the large electronegativity difference between the atomic top layer and bottom layer of the XN-MO sheet induces the out-of-plane dipolar polarization, leading the out-of-plane piezoelectric effect. The flexible SnN-InO with remarkable out-of-plane piezoelectric properties can be applied in nanoscale energy harvesting devices and nano-sensor in medical devices. [ABSTRACT FROM AUTHOR]

The piezoelectricity of functionalized MXenes is of increasingly interest in theoretical and experimental research due to many advantages, such as narrowing the electromechanical coupling size, enhancing the piezoelectric coefficients and producing the out-of-plane piezoelectricity. In this work, employing the first-principle calculations, the piezoelectricity together with related electronic and elastic properties of six functionalized MXenes Sc 2 CTT′ monolayers where T and T′ are functional groups were comprehensively investigated. All of them are mechanically stable and more flexible than graphene, indicating their potential use in flexible devices. Furthermore, the semiconducting nature and broken inversion symmetry endow them with piezoelectricity for nanoelectromechanical facilities. In terms of the in-plane piezoelectricity, Sc 2 CFCl possesses the biggest d 22 and Sc 2 COHH has the biggest d 15. Sc 2 CHCl and Sc 2 CFCl monolayers have stronger out-of-plane piezoelectricity when the strain is applied along the x axis due to their larger absolute value of d 31 than other monolayers. In addition, with relative to MoSTe which has relatively good out-of-plane piezoelectricity, Sc 2 COHF and Sc 2 CHCl monolayers possess comparable out-of-plane piezoelectric strain coefficient d 33 , which is favorable for their applications in out-of-plane piezoelectric sensing. Excitingly, the value of d 33 (35.64 pm/V) for Sc 2 COHH monolayer is surprisingly over three times of that for MoSTe. It is expected that the studied Sc 2 CTT' monolayers with commendable piezoelectric properties can be utilized in certain nanoelectromechanical systems, such as the blood-pressure meter, bionic skin of robots and energy harvesting equipments. • Sc 2 CTT′ monolayers are mechanically stable and more flexible than graphene. • The broken inversion symmetry endows Sc 2 CTT′ monolayers with piezoelectricity. • Sc 2 COHH, Sc 2 COHF and Sc 2 CHCl have considerable out-of-plane piezoelectricity. • Sc 2 COHH monolayer possesses surprising d 33. • The electronic and ionic contributions to the piezoelectric coefficients are analyzed. [ABSTRACT FROM AUTHOR]

Wehave developed a new method to fabricate multilayer films, which usesprepared thin films as modular blocks and transfer as operation modeto build up multilayer structures. In order to distinguish it fromthe in situ fabrication manner, this method is called modular assemblyin this study. On the basis of such concept, we have fabricated amultilayer film using the silver mirror film as the modular blockand poly(lactic acid) as the transfer tool. Due to the special double-layerstructure of the silver mirror film, the resulting multilayer filmhad a well-defined stratified architecture with alternate porous/compactlayers. As a consequence of the distinct structure, the interactionbetween the adjacent layers was so weak that the multilayer film couldbe layer-by-layer stripped. In addition, the top layer in the filmcould provide an effective protection on the morphology and surfaceproperty of the underlying layers. This suggests that if the surfaceof the film was deteriorated, the top layer could be peeled off andthe freshly exposed surface would still maintain the original function.The successful preparation of the layer-by-layer strippable silvermultilayer demonstrates that modular assembly is a feasible and effectivemethod to build up multilayer films capable of creating novel andattractive micro/nanostructures, having great potential in thefabrication of nanodevices and coatings. [ABSTRACT FROM AUTHOR]

Abstract: Four novel Zn(II) complexes [Zn(L1)(bipy)(H2O)2]·4H2O(1), [Zn(L1)(phen)(H2O)2]·4H2O(2), [Zn(L2)(bipy)(H2O)2]·4H2O(3) and [Zn(L2)(phen)(H2O)2]·4H2O (4), where bipy=2,2′-bipyridine, phen=1,10-phenanthroline, L1 =2,2′-bipyridine 5,5′-dicarboxylic acid, L2 =2,2′-bipyridine-4,4′-dicarboxylic acid, have been synthesized and characterized using IR, 1H NMR, element analysis and single-crystal X-ray diffractometry. The unit cell parameters for the title complex (1), a =7.9621(10)Å, b =12.6853(17)Å, c =13.3714(17)Å, α =68.549(2)°, β=79.065(2)°, γ =88.723(2)°, V =1232.5(3)Å3, Z =15, space group,P-1(2).complex (4) a =9.5710(5)Å, b =14.1140(7)Å, c =19.0045(9)Å, α =90°, β =99.9920(10)°, γ =90°, V =2528.3(2)Å3, Z =32, space group, P121/n 1(14). The binding of the complexes with fish sperm DNA (FS-DNA) was investigated by electronic absorption spectra and fluorescence spectroscopy, showing that the complexes have the ability of interaction with DNA of intercalative mode. The intrinsic binding constant K of the complexes with FS-DNA is 0.37×105 M−1 (1) 0.73×105 M−1 (2), 0.98×105 M−1 (3), and 1.05×105 M−1 (4). The results indicate that the four complexes bound to DNA with different binding affinity, in the order complex 4 > 3 > 2 > 1. Gel electrophoresis assay demonstrates the ability of the complexes to cleave the pBR322 plasmid DNA. The cytotoxic activity of the complexes was tested against four different cancer cell lines. The four complexes exhibited cytotoxic specificity and significant cancer cell inhibitory rate. [Copyright &y& Elsevier]

Abstract: Two novel complexes, namely, [Pd(pdc)2]·(dmp)·6H2O (1) and [Pd(pdc)2K(H2O)5·3H2O]n (2) [H2pdc=pyridine-2,3-dicarboxylate acid, dmp=2,9-Dimethyl-1,10-phenanthroline] were synthesized and characterized as pH-dependent products. Gel electrophoresis assay demonstrated the ability of the complexes to cleave the pBR 322 plasmid DNA. Values of IC50 calculated for complexes 1 and 2 show that the two complexes exhibit good cytotoxic activity against different cell lines tested in general, especially more effective against HL-60 and A2780cisR cell lines. [Copyright &y& Elsevier]

Sishen Wan (SSW) is a commercial and frequently used Chinese patent medicine listed in the Chinese Pharmacopeia, which is usually used to treat chronic colitis. We explored the pharmacological mechanism of Sishen Wan attenuated experimental chronic colitis by inhibiting Wnt/β-catenin pathway. Experimental chronic colitis was induced by trinitrobenzene sulfonic acid (TNBS). The therapeutic effect of SSW were analyzed by index of colonic weight, colonic length, pathological score. Cytokines expression were analyzed by ELISA, while the apoptosis level was checked by TUNEL staining. These proteins of Wnt/β-catenin signaling pathway was analyzed by Western blot assay. Rats with TNBS-induced chronic colitis were treated by SSW for 10 days. The efficacy of SSW was demonstrated by improved macroscopic and microscopic colonic damage. SSW increased the level of ATP in colonic mucosa, while SSW inhibited β-catenin, ubiquitination of Nemo-like-kinase-associated ring finger protein and T-cell factor, and expression of Wnt/β-catenin downstream proteins (including c-Myc, cyclo-oxygenase-2, cyclin D1, survivin, signal transducer and activator of transcription 3 and zipper-interacting protein kinase), and improved lymphoid enhancer factor ubiquitination and β-TrCP activity, followed by excessive apoptosis of colonic epithelial cells. SSW effectively attenuated experimental chronic colitis induced by TNBS, which was realized by inhibition of the Wnt/β-catenin signaling pathway. Image 1 [ABSTRACT FROM AUTHOR]