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F16 is a mitochondria-targeted, broad-spectrum anticancer agent in the pre-clinic cancer therapy. Here we developed two fluorescent isomers of F16 (o-F16 and m-F16) with entirely different photophysical properties, uncoupling activity, and cytotoxicity by merely modifying the linking orientation of pyridinium and indole units. Individually, o-F16 acted as a strong uncoupler to reduce the mitochondrial respiration efficiency, while m-F16 could hardly uncouple the mitochondrial respiration due to its poor proton dissociation capability. Owing to their intrinsic fluorescence, o-F16 and m-F16 could specifically image mitochondria in the green and red channel, respectively. This work could provide useful information for the development of uncouplers and design of mitochondrial-targeted drugs.

A green Passerini three-component reaction of 2-(4-oxo-4,5,6,7-tetrahydro-1 H -indol-1-yl)acetic acid with alkyl or aryl isocyanides and aldehydes was reported under aqueous conditions at 35 °C for 1 h, and 21 indolone- N -amino acid derivatives were prepared in high yields of 42%–99%. Their structures were characterized by IR, ESI–MS, NMR and elemental analysis, and the possible mechanisms have been also proposed. The highly efficient and eco-friendly method provides a facile access to a library of indolone- N -amino acid derivatives for future research on bioactivity screening.

Underground coal mining inevitably results in land surface subsidence. Acquiring information on land surface subsidence is important in the detection of surface change. However, conventional data acquisition techniques cannot always retrieve information on whole subsidence area. This study focuses on the reconstruction of a digital elevation model (DEM) with terrestrial laser scanning (TLS) point cloud data. Firstly, the methodology of the DEM with terrestrial 3-dimensional laser scanning is introduced. Then, a DEM modeling approach that involves the application of curved non-uniform rational B-splines (NURBS) surface is put forward. Finally, the performance of the DEM modeling approach with different surface inverse methods is demonstrated. The results indicate that the DEM based on the point cloud data and curved NURBS surface can achieve satisfactory accuracy. In addition, the performance of the hyperbolic paraboloid appears to be better than that of the elliptic paraboloid. The reconstructed DEM is continuous and can easily be integrated into other programs. Such features are of great importance in monitoring dynamic ground surface subsidence.

Heavy metal (HM) tolerance, effects on maize growth, heavy metal absorption and accumulation by endophytic Peyronellaea from HM-contaminated and uncontaminated sites were studied to evaluate the hypothesis that endophytes from HM-contaminated sites would enhance HM-tolerance in hosts. Although we found that certain endophytes improved tolerance of plants to heavy metals, isolates from the HM-contaminated site were not more tolerant to heavy metals than those from the uncontaminated site. Pot experiments indicated that growth and heavy metal absorption and accumulation by host plants in HM-polluted environments could be affected by inoculation with HM-tolerant endophytic fungi, and isolates showed a high intraspecific variability. However, there was no significant difference in growth between the maize inoculated with the endophytes from the HM-contaminated site and uncontaminated site under lead stress. Similarly, the HM content in the shoots and roots of maize inoculated with the isolates from the HM-contaminated site was not always higher than that in maize inoculated with endophytes from the uncontaminated site. Therefore, based on our experiments it is suggested that HM-tolerance due to endophytes and their effects on host plant growth and heavy metal absorption and accumulation were not correlated with origin of the endophytes.

In this paper, aiming at the trans-membrane transport properties of the different DLCs related with the cytotoxicities, we have studied photophysics of DLCs in RMs. MTT assays indicated that DLC 1 were more cytotoxic than DLC 2 and 3. Steady-state absorption and fluorescence method have been used to characterize the binding model of three DLCs (1, 2, and 3) in RMs and bovine serum albumin (BSA). The progressive red-shift of compound 1 indicated that it can experience the hydrophilic and hydrophobic environment owing to the rigid structure, thus it can more easily cross the double membrane of cell than compounds 2 and 3. In conclusion, we simulated a model of compound 1 in RMs. The present study of F16 derivatives in microenvironment would provide some useful information to the cell membrane simulation and design of DLCs.

This paper investigates the interactions between human serum albumin (HSA) and CdTe quantum dots (QDs) with nearly identical hydrodynamic size, but capped with four different ligands (MPA, NAC, and GSH are negatively charged; CA is positively charged) under physiological conditions. The investigation was carried out using fluorescence spectroscopy, circular dichroism (CD) spectra, UV–vis spectroscopy, and dynamic light scattering (DLS). The results of fluorescence quenching and UV–vis absorption spectra experiments indicated the formation of the complex of HSA and negatively charged QDs (MPA-CdTe, NAC-CdTe, and GSH-CdTe), which was also reconfirmed by the increasing of the hydrodynamic radius of QDs. The K a values of the three negatively charged QDs are of the same order of magnitude, indicating that the interactions are related to the nanoparticle itself rather than the ligands. Δ H S > 0 implied that the electrostatic interactions play predominant roles in the adsorption process. Furthermore, it was also proven that QDs can induce the conformational changes of HSA from the CD spectra and the three-dimensional fluorescence spectra of HSA. However, our results demonstrate that the interaction mechanism between the positively charged QDs (CA-CdTe) and HSA is significantly different from negatively charged QDs. For CA-CdTe QDs, both the static and dynamic quenching occur within the investigated range of concentrations. According to the DLS results, some large-size agglomeration also emerged.

The diversity and metal tolerance of endophytic fungi from six dominant plant species in a Pb–Zn mine wasteland in Yunnan, China were investigated. Four hundred and ninety-five endophytic fungi were isolated from 690 tissue segments. The endophytic fungal colonization extent and isolation extent ranged from 59 % to 75 %, and 0.42–0.93, respectively, and a positive correlation was detected between them. Stems harboured more endophytic fungi than leaves in each plant species, and the average colonization extent of stems was 82 %, being significantly higher than that of leaves (47 %) (P ≤ 0.001, chi-square test). The fungi were identified to 20 taxa in which Phoma, Alternaria and Peyronellaea were the dominant genera and the relative frequencies of them were 39.6 %, 19.0 % and 20.4 %, respectively. Metal tolerance test showed that 3.6 mM Pb2+ or 11.5 mM Zn2+ exhibited the greatest toxicity to some isolates and they did not grow on the metal-amended media. In contrast, some isolates were growth stimulated in the presence of tested metals. The isolates of Phoma were more sensitive to Zn2+ than the isolates of Alternaria and Peyronellaea. However, the sensitivity of isolates to Pb2+ was not significantly different among Phoma, Alternaria, Peyronellaea and other taxa (P > 0.05, chi-square test). Our results suggested that fungal endophyte colonization in Pb–Zn polluted plants is moderately abundant and some isolates have a marked adaptation to Pb2+ and Zn2+ metals, which has a potential application in phytoremediation in this area.

Chlorpyrifos (CPF) is a widely used organophosphate insecticide which could bind with human serum albumin (HSA) and bovine serum albumin (BSA). The binding behavior was studied employing fluorescence, three-dimensional fluorescence, Circular dichroism (CD) spectroscopy, UV-vis absorption spectroscopy, electrochemistry and molecular modeling methods. The fluorescence spectra revealed that CPF causes the quenching of the fluorescence emission of serum albumin. Stern-Volmer plots were made and quenching constants were thus obtained. The results suggested the formation of the complexes of CPF with serum albumins, which were in good agreement with the results from electrochemical experiments. Association constants at 25°C were 3.039 × 10(5) mol L(-1) for HSA, and 0.3307 × 10(5) mol L(-1) for BSA, which could affect the distribution, metabolism, and excretion of pesticide. The alterations of protein secondary structure in the presence of CPF were confirmed by the evidences from UV and CD spectra. Site competitive experiments also suggested that the primary binding site for CPF on serum albumin is close to tryptophan residues 214 of HSA and 212 of BSA, which was further confirmed by molecular modeling.

The triaxial creep experiment of artificially frozen soil in deep alluvium was performed by a self-developed machine of triaxial creep frozen soil. After analyzing the experiment results, applying parabolic yield criterion for improved viscoplasticity in the Nishihara model, a new creep constitutive model was established for describing frozen-soil's creep characteristics under high confining pressures. The secondary development tools and data interface had been used to add the visco-elastic-plastic creep constitutive model to standard ADINA FEM. Numerical simulation of the shaft well excavation process and field measurement displacements of frozen wall were performed in the mine; and the results showed that the visco-elastic-plastic creep constitutive model was suitable and reasonable. This constitutive model could be significance for the frozen soil structure long-term stability analysing and the displacement forecasting.

The glass substrates containing metal Ag nanoparticles (NPs) were fabricated by electric field-assisted ion diffusion process. The Er3+–Yb3+-codoped tellurite thin films were deposited on these substrates via non-hydrolytic sol–gel method. The effect of metal Ag NPs embedded in glass substrates on up-conversion luminescence of tellurite thin films was investigated. It was found that the up-conversion luminescence of thin film was significantly enhanced by the metal Ag NPs embedded in glass substrates. The reverse electric field-assisted ion diffusion process was also applied to induce the migration and aggregation of the metal Ag NPs. As the metal Ag NPs aggregated closer towards the surface layer of glass substrates, the larger enhancement effect of up-conversion luminescence was achieved. The enhancement factors for green emission increased from dozens up to hundreds of times. This work provides a novel pathway for surface-plasmon-enhanced up-conversion luminescence. And a new application for the electric field-assisted ion diffusion process was also opened up through this work.

To solve the problem of the extremely high hydrolytic reactivity of tellurium alkoxides in hydrolytic sol–gel method, the nonhydrolytic sol–gel process has been applied as a novel route for producing TeO2 based thin films. The transition of nonhydrolytic sol–gel was monitored by means of 1H NMR, FT-IR and Raman techniques. These results show that the formation of Te–O–Te bonds in gel networks mainly resulted from the nonhydrolytic cross-condensation reaction between different Te–OR groups. The decomposition process and structure evolution of the nonhydrolytic gel products were investigated and managed. Results from DTA and XRD analyses show that metallic tellurium, β-TeO2 and α-TeO2 phase appeared in the film during heat-treatment process at around 300, 350 and 400 °C, respectively. The formation of metallic tellurium can be alleviated through preheating the gel films under O2 atmosphere or by additions of the second component. Crystallization of α-TeO2 could be retarded by additions of TiO2 or Al2O3, and the transparent, homogeneous amorphous TeO2 based thin films were obtained by the methods above. The nonhydrolytic sol–gel process developed in this study offers a simple and practical method for fabricating TeO2 based thin film devices.