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Introduction Bufalin is a component of Chinese traditional medicine, Chansu, which is reported to induce cell death among various kinds of tumors. Apoptosis evasion is a common problem of cancer treatment. Materials and methods The proliferation of U-87 and U-373 treated by bufalin combined with or without apoptosis inhibitor was detected by MTT assay. The protein levels related to apoptosis and necroptosis were measured by Western blotting. Immunoprecipitation (IP) was applied for monitoring the formation of necrosome. The gene knockdown by CRISPR/Cas9 was applied to determine the roles of the proteins in apoptosis and necroptosis. Results In this study, we found that bufalin could induce apoptosis or necroptosis when U-87 and U-373 escaped from apoptosis. Bufalin triggered cell death by upregulating tumor necrosis factor (TNF) -α, TNF receptor 1 (TNFR1) and receptor-interacting protein 1 (RIPK1). Antagonizing cellular inhibitor of apoptosis 1 (cIAP1) and cIAP2 were also contributory. Caspase-8 activation led to apoptosis. When caspase-8 was functionally lost, necrosome consisted of RIPK1, receptor-interacting protein 3 (RIPK3) and mixed lineage kinase domain-like protein (MLKL) formed and necroptosis happened. The knockdown of above genes or the drug treatment confirmed the mechanism of bufalin-induced cell death. Cytotoxicity of bufalin to caspase-8 knockdown cell lines made control cell lines more sensitive to bufalin in their mixture. Discussion The cytotoxicity of bufalin to U-87 and U-373 was by inducing apoptosis or necroptosis when they were sensitive to apoptosis or not. The results indicated that seeking for treatments that could induce apoptosis and necroptosis was a good solution for the tumor evasion of apoptosis.

A highly crystalline nanosized spinel LiMn2O4/3DG composite cathode material for high rate lithium ion batteries was successfully prepared by mixing spinel LiMn2O4 particles with reduced graphene oxide (3DG). Spinel LiMn2O4 and reduced three-dimensional graphene oxide were synthesized using a hydrothermal method and freeze-drying technology, respectively. The structure, morphology and electrochemical performance of the synthesized materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge–discharge techniques. The results showed that the LiMn2O4/3DG composites exhibited excellent rate capability and stable cycling performance. The discharge capacity was 131 mA h g−1 and the capacity remains at 89.3% after 100 cycles at a 0.5 C rate, while the discharge capacity was 90 mA h g−1 at 10 C. Compared with spinel LiMn2O4 materials, the LiMn2O4/3DG composites showed obvious improvement in electrochemical performance.

This paper describes a simple and efficient electrochemical assay for the determination of trace Cu(II) employing L-cysteine functionalized gold nanoparticles/CdS nanospheres/glassy carbon electrode (L-cys/AuNPs/CdS/GCE) as an enhanced sensing platform. The prepared sensor exhibited a high active surface area, excellent electron transfer properties, and greatly enhanced sensitivity for Cu(II) in comparison with AuNPs/CdS/GCE, L-cys/AuNPs/GCE and CdS/GCE, due to the synergistic effect of L-cysteine, Au nanoparticles and CdS nanospheres. The experimental conditions, namely preconcentration time, electrolyte and pH value, were optimized in order to maximize the sensitivity of the measurements. Under optimal conditions, the SWASV stripping signals for Cu(II) were linear in the concentration range of 0.5 to 200.0 nmol L−1, and a detection limit of 0.1 nmol L−1 (S/N = 3) was obtained. The prepared sensor also exhibited excellent repeatability and selectivity for Cu(II) over competing environmentally relevant metal ions. It was further applied to determine Cu(II) in real water samples, and the results agreed satisfactorily with the certified values.

In this study, a noninvasive experimental method and a discrete element method (DEM) model were used to investigate the micro–macro behavior of TATB granules including global deformations, contact forces, stress distributions, local coordination number, local pore ratio, particle kinematics, and granule displacement during compacting process. The TATB granule deformation and structural evolution during compaction process were studied by X-ray tomography and the deformation characteristics of deformable material. The size and number of granules with different sizes were determined from the CT images. The digital microstructure can be directly used for the numerical simulation setup. The DEM method was used for the numerical simulation of TATB granules during compaction. The contact forces and displacement vectors in compaction process were obtained. The behaviors and stress distributions at different pressures were also derived from the simulation. This study evaluated the possibility to better describe the behaviors of TATB granules.

The first highly enantioselective conjugate addition of 2-acetyl azaarenes to α-substituted-β-nitroacrylates was successfully realized under mild conditions by a Ni(II)-bisoxazoline complex, providing the desired adducts bearing an all-carbon quaternary stereocenter in high yield with excellent enantioselectivity. The products obtained in this system could be readily converted into optically active β2,2-amino esters, succinates, lactones, and lactams.

Amorphous silicon thin-film PV cell(AST) generally consists of a few – micron thick silicon film on a glass substrate, which has difficulty for being accurately measured by using a conventional testing method to obtain its elastic modulus and hardness. In our study, we are applying nanoindentation for the measurement purpose and divide the sample into five regions for studying. Both of peak load - and loading rate - dependences supervise us to more accurately measure the mechanical properties of silicon layer through defining the peak load at 9000μN and loading rate at 1000μN/s. It was also observed that across the whole sample measurements on the elastic modulus have much better consistence than those on the hardness. We therefore propose a method of partitioning the sample into two parts for counting the different hardness measurements.

Two new zinc(II) metal-organic compounds, {[Zn(ADC)(bib)]·CH3OH·H2O}n (1) and [Zn(ADA)(bib)]n (2) (H2ADC = 1,3-adamantanedicarboxylic acid, H2ADA = 1,3-adamantanediacetic acid, bib = 1,4-bis(2-methyl-imidazol-1-yl)butane), have been synthesized and characterized. In 1, zinc(II) ions are bridged by ADC to form a 1-D chain. The chains are further connected by bib to form a 2-D wave structure. In 2, zinc(II) ions are bridged by two ADA to form a 1-D looped chain, and then the 1-D looped chain is connected through bib resulting in a 2-D network. Fluorescent properties, TG analysis, and XRPD for 1 and 2 are also measured and discussed.

Though hot embossing is a well known technique for the fabrication of polymer based micro-device, the deformation behavior of solid polymer during hot embossing process is not investigated clearly. In this paper, the deformation behavior of solid polymer was observed by two methods, synchronous observation and asynchronous analysis. A finite element simulation and a phenomenological model were used to evaluate the deformation behavior of solid polymer during hot embossing. Results showed that the deformation of solid polymer during embossing process included two stages. One was a stress concentration and strain hardening stage, which occurred during the heating and applying pressure process. The ''swallowtails'' induced by incomplete filling generate at this stage. The other was a stress relaxation and deformation recovery stage, which occurred during the remaining temperature and pressure process. The ''swallowtails'' were eliminated at this stage. The second stage was significant for improving replication precision, but it had not been reported before.

Defect directional curvature KD-def was proposed as a reasonable criterion for the reactivities and adduct structures at the defective region of single-walled carbon nanotubes (SWCNTs). B3LYP/6-31G* calculations for the [2 + 1] and [1 + 1] additions of a series of 11-layer (n, n) (n = 4–8) and six-layer (10,0) SWCNTs with Stone-Wales defects showed that the KD-def or its mean KM-def was a good index to judge the adduct structures and the reactivities. Adducts of the [2 + 1] additions were divided into two types: one was the adduct with the C-X-C configuration and corresponding to the large KD-def and the large binding energy, and another was the adduct with the closed −3MR structure and corresponding to the small KD-def and the small binding energy. It must be pointed out that, besides mainly relying on the KD-def, the adduct structures and the reactivities of the [2 + 1] additions had been weakly affected by topologic structures. The calculated results for the [1 + 1] additions of the 11-layer (5,5) SWCNT with defect A revealed that the binding energies monotonously increased with the KM-def. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009

Excised leaves of kidney bean (Phaseolus vulgaris) were used to investigate the mechanism of NO generation under UV-B stress. We showed that two signaling molecules, NO and H2O2, were produced in the irradiated leaves. NO release was blocked by LNNA, an inhibitor of NOS. Application of CAT (EC 1.11.1.6) not only effectively eliminated H2O2 in the leaves, but also inhibited the activity of NOS and the emission of NO. In contrast, treatment with exogenous H2O2 increased both of those events. Therefore, we suggest that, under UV-B stress, NO production is mediated by H2O2 through greater NOS activity.

A series of novel calix[4]arenocrown derivatives 8a–8c in a cone conformation, in which the lower rim and the upper rim were connected via ring-closing metathesis (RCM) reaction have been synthesized in good yields, and their structures were characterized by 1H NMR, 13C NMR, IR, MALDI-TOF MS techniques and elemental analyses.

A series of novel calix[4]arenocrowns 1a – c were efficiently synthesized by a one-pot reaction of calix[4]monohydroquinone diacetate 5 with ditosylate 6 and its analogues in the presence of sodium hydroxide. It was found that the calix[4]arenocrowns could form stable pseudorotaxane-type complexes 2a – c with paraquat, and further self-assemble into calix[4]areno[2]catenanes 3a – c with dicationic salt 8 and p -bis(bromomethyl)benzene.

We report on the preparation of nanostructured Ag-Bi alloy thin films by galvanostatic electrodeposition in organic baths, which also provides a very good way to prepare the nanostructured active metal alloy thin films. Control of the current densities and relative concentrations of the cations allowed the diameters of Ag-Bi nanocrystallites to be specified in the range of 20-50 nm. The surface morphologies of the films electrodeposited in an organic dimethysulfoxide bath containing 0.01 mol/L Bi(NO 3 ) 3 -0.01 mol/L AgClO 4 -0.1 mol/L LiClO 4 with a current density of 1.0 mA/cm 2 were uniform in metallic luster, and the films were adhesive. The results of X-ray diffraction measurements indicated that the nanostructured Ag-Bi thin films were the mixture of silver-rich solid solution phase and pure bismuth phase. The optical absorptance spectra of the nanostructured Ag-Bi thin films were broader, and increased in magnitude and shifted toward lower energies for increasing Ag content in the Ag-Bi thin films. The resistivities of the films decreased with the thickness increasing.

We have shown hollow Ni nanonodules with outer diameters of 80-200 nm and wall thicknesses of 5-25 nm could be prepared by electrochemical deposition in the NiCl2 + dimethyl sulfoxide + C2H4O3 + H2O system, and the products were high purity. In particular, Ni hollow nanonodule structures or highly assembling Ni hollow nanostructures can be selected by varying the compositions of the solvent mixture. Apart from the hollow grain size, the wall thickness can also easily be controlled by varying the electrochemical parameters, salt concentration, and deposition time. The typical coercivity of Ni hollow nanostructures with particle sizes of about 100-150 nm was much bigger than that of the bulk Ni.

In this article, electrospinning of poly (ethylene oxide) (PEO) /egg white blend and that of poly (carbon dioxide-co-propylene oxide) were studied. Blend fibrous mats containing poly (carbon dioxide-co-propylene oxide) and PEO/egg white blend were obtained through multi-jet and component alternate eletrospinning, respectively. Component alternate electrospinning exhibits higher efficiency and produces better blended products than multi-jet electrospinning does because the inter-influence between different jets during multi-jet electrospinning greatly affects electrospinning process while component alternate electrospinning avoids such kind of influence.

The synthesis, structure and ring-closing metathesis (RCM) reactions of polyether bridged biscalix[4]arenes 6 in the partial cone conformation with upper rim allyl substituents are reported. The RCM reaction modes depend on the length of polyether chain. Diethylene glycolic chain produced the dimer 7a and linear oligomer 7a′ with multi-cavities, whereas triethylene and tetraethylene glycolic chains allowed direct cyclization through intramolecular head-to-tail pattern to yield novel bridged biscalix[4]arenes 7b–c .

The reaction of bisbenzimidazolium salt with Grignard reagents and a new synthetic method of a-diketones from bis-benzimidazolium salt and Grignard reagents are reported. The structures of all a-diketones are characterized by elemental analyses, infrared spectroscopy and 1H NMR spectroscopy. The influences of the various Grignard reagents on the yield of a-diketones and the mechanism are discussed, and a new convenient synthetic method for a-diketones is provided.

Silicon insert is a promising tool for microinjection moulding (MIM). However, its fracture problem induced by impact in MIM creates a bottleneck for application. The purpose of this paper is to investigate the impact behaviour in MIM and the effect on the fracture of silicon inserts. The finite element method is utilised to calculate the crack propagation of silicon inserts with pressure load and thermal load in the MIM process. The simulation result shows that the crack propagation is more easily induced by the increase of pressure load, while the temperature change has little effect on the crack propagation. An experimental platform, including a novel rotatable insert mould, is developed to investigate the dynamic pressure in the MIM process. The result shows that both the maximum pressure and the maximum loading rate occur in the initial period of MIM process. It indicates that the silicon insert is more prone to fracture at the beginning of the MIM process, and spatial pressure peaks are observed in the cavity as well. The nearly consistent distribution between the peak positions and the insert fracture zones shows that the pressure distribution is quite relevant to the fracture of the silicon insert. The result is helpful because it reveals the fracture phenomenon of silicon inserts.

The process in which the helium-radon clusters come into being was discussed.According to the traditional theory of mechanics,the theoretical calculation formula of vertical migration velocity for helium-radon clusters has been deduced.The maximal velocity and the time needed for the helium-radon clusters being accelerated to the maximal velocity are also given.