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Reduced drug uptake and elevated drug efflux are two major mechanisms in cancer multidrug resistance (MDR). In the present study, a new multistage O

In order to further understand the corrosion mechanism of reinforcement and simulate the natural corrosion phenomenon, we use X-ray computed tomography (XCT) to nondestructively trace and analyze the corrosion process of the specimens containing the initial defect in protective layer. We compare three-dimensional corrosion morphology and damage of specimens containing interface, middle and surface defects under two accelerated corrosion experiments: the applied current experiment and the wet-dry cycles (W/D) experiment.The results show that W/D tends to produce spatially randomly distributed large pits, while energization produces uniformly distributed tiny pits. W/D corrosion produces generally larger crack widths at similar actual corrosion degree than those with energized accelerated corrosion, which is closer to the natural corrosion. The effects of different defect locations and accelerated corrosion methods on the accumulation of interfacial corrosion products are not obvious, but the cover cracking is obviously related to the defect location, the closer the defect is to the outside of the specimen, the more likely it leads to the cracking of specimen.

The construction of high-efficiency tumor theranostic platform will be of great interest in the treatment of cancer patients; however, significant challenges are associated with developing such a platform. In this study, we developed high-efficiency nanotheranostic agent based on ferroferric oxide, manganese dioxide, hyaluronic acid and doxorubicin (FMDH-D NPs) for dual targeting and imaging guided synergetic photothermal-enhanced chemodynamic/chemotherapy for cancer, which improved the specific uptake of drugs at tumor site by the dual action of CD44 ligand hyaluronic acid and magnetic nanoparticles guided by magnetic force. Under the acidic microenvironment of cancer cells, FMDH-D could be decomposed into Mn

The characteristics of dissolved organic matter (DOM) in the influent and secondary effluent from 6 municipal wastewater treatment plants (WWTPs) were investigated with a size exclusion chromatogram (SEC) coupled with multiple detectors to simultaneously detect ultraviolet absorbance, fluorescence, dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) as a function of molecular weight (MW). The SEC chromatograms showed that biopolymers (6 kDa) and humic substances (0.5-6 kDa) comprised the significant fraction in the influent, while humic substances became the abundant proportion in the secondary effluent. Direct linkages between MW distribution and hydrophobicity of DOM in the secondary effluent were further explored via SEC analysis of XAD resin fractions. DON and DOC with different hydrophobicity exhibited significantly distinct MW distribution, indicating that it was improper to consider DOC as a surrogate for DON. Different from DOC, the order of averaged MW in terms of DON was hydrophobic neutral ≈ transphilic neutral hydrophobic acid transphilic acid hydrophilic fraction. Fluorescence spectral properties exhibited a significant semi-quantitative correlation with MW and hydrophobicity of DOC, with Pearson's coefficients of -0.834 and 0.754 (p 0.01) for biopolymer and humic substances. Meanwhile, regional fluorescence proportion was demonstrated to indicate the MW and hydrophobicity properties of DON at the semi-quantitative level. The fluorescence excitation-emission matrix (EEM) could be explored to provide a rapid estimation of MW distribution and hydrophobic/hydrophilic proportion of DOC and DON in WWTPs.

The effect of initial defects on the surface of concrete cover with different sizes on the corrosion cracking time of steel bars was studied by electrochemical acceleration method. The results show that the initial defects on the surface of the concrete cover will significantly shorten the cracking time of the cover and have a strong induction effect on the cracking direction. The degree of cracking time reduction is positively correlated with the length of surface defects. At the engineering site, attention should be paid to the surface quality of the concrete structure. Then, the paper also evaluated the effect of the thickness of the sheath and the diameter of the steel bar on the cracking time of the cover.

The synthesis of anisotropic branched gold nanoparticles remines to be challenging as their arm number and arm length could hardly be controlled, greatly limited their biomedical application. We report the large-scale high-yield synthesis of PdCu@Au tripods, and, for the first time, their two-photon luminescence properties with quantitative characterization of the two-photon action cross section as well as quantum yield. By introducing nitrogen protection to the synthesis of the PdCu bimetallic cores, this approach eliminates the oxidative etching caused by oxygen in the air, providing a 2.5 times higher synthetic yield of 70.4 %, which enables the large-scale preparation of PdCu@Au at ca. 380 mg per batch. By the conformal coating of PdCu bimetallic cores, the PdCu@Au tripods are prepared with a purity of >90 % with average arm length 45.3 ± 5.6 nm that is ideal for biomedical applications. The PdCu@Au tripods demonstrate a much brighter two-photon luminescence than that from Au nanorods, with a 3.6 ± 0.9 times larger two-photon action cross section and comparable quantum yield. Our result also shows the two-photon luminescence property of PdCu@Au tripods could be tuned by their distinct localized surface plasmon resonance property and, in turn, the different amount of Au coating. This tunability could be explained by the recently-proposed two-step excitation mechanism of two-photon luminescence in Au nanoparticle. The folate-targeted in vitro two-photon luminescence imaging of MDA-MB-435 breast cancer cells were also demonstrated to show the great potential using PdCu@Au tripods as novel multi-functional platforms for cancer theranostics.

To observe the effect of electroacupuncture (EA) therapy on levels of oxygen free radicals (OFR) and hippocampal apoptosis-related protein expression in ischemic learning-memory disorder rats so as to investigate its mechanisms underlying improvement of ischemic learning-memory impairment.A total of 60 SD rats were randomly divided into sham operation (sham), model, medication, and EA groups, with 15 rats in each group. The learning-memory disorder model was made by occlusion of bilateral carotid arteries. EA (2- 3 Hz, 2 mA) was applied to "Zhi San Zhen" ["Shenting" (GV 24) and bilateral "Benshen" (GB 13)] for 30 min, once a day for 3 weeks. The rats of the medication group were treated by lavage of Aricept (0.03 mg . kg(-1) . d(-1)), once daily for 3 weeks. The rats' learning-memory ability was detected by Morris water maze tests and the state of hippocampal apoptosis cells was observed by light microscope after TUNEL staining and the expression of hippocampal Bcl-2, Bax and Caspase-3 proteins was detected by immunohistochemistry. Serum and hippocampal superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity and malondialdehyde (MDA) contents were detected by chemical colorimetric analysis.Compared with the sham group, the escape latencies (place-navigation) after modeling were evidently prolonged, and the times of target-platform crossing in 90 sec (spatial probe test) considerably reduced in the model group (P0.01), suggesting an impairment of learning-memory ability. After the treatment for 21 d, the increased escape latency and the reduced target-platform crossing time in both EA and medication groups were reversed in comparison with the model group (P0.01), suggesting an improvement of memory ability, and the effect of the EA group was significantly superior to that of the medication group (P0.05). Compared with the sham group, the number of apoptotic cells in hippocampal CA 1- CA 3 regions, and the expression levels of hippocampal Bcl-2, Bax and Caspase-3 proteins, and serum and hippocampal MDA contents were significantly increased in the model group (P0.01), while serum and hippocampal SOD and GSH-Px levels obviously decreased in the model group (P0.01). After the treatment for 21 days, compared to the model group, the number of the apoptotic cells, the expression levels of hippocampal Bax and Caspase--3 proteins, and the contents of serum and hippocampal MDA were notably decreased in the EA and medication groups (P0.01), whereas, Bcl-2 protein expression levels, and serum and hippocampal SOD and GSH-Px activity were notably up-regulated in the EA and medication groups (P0.01). The effects of EA group were obviously superior to those of medication group in increasing hippocampal Bcl-2 immunoactivity, serum SOD and GSH-Px and hippocampal GSH-Px activity and in down-regulating serum MDA level (P0.01, P0.05).Electroacupuncture intervention can improve learning-memory ability in ischemic learning-memory disorder rats which may be associated with its effects in reducing blood and hippocampal OFR contents and hippocampal cellular apoptosis.

Lanthanide nanoparticles (NPs), characterized by their large Stokes’ shifts, narrow emission bands and high photochemical stability, are promising candidates for optical probes in biological research. As a typical red emission material, Eu3+-doped YVO4 is investigated in pursuit of an integral methodology for Ln-based bioprobes. Assisted with phosphino-polyacrylic acid, YVO4:Eu NPs with a luminescent quantum yield of ca. 54% are synthesized via a one-pot hydrothermal reaction. The obtained NPs exhibit good water/buffer stability and feasible biomodification benefiting from the surface carboxylic acid groups. However, having an inorganic core of ca. 20 nm, these NPs do not affect the conformation of surface conjugated proteins (bovine serum albumin), as confirmed with the circular dichroism spectrum. A specific recognition protocol is demonstrated by biotinated YVO4:Eu NPs in quantitative fluoroimmunoassay and microchip assay. Furthermore, the biocompatibility of the Ln NPs, which is an important aspect towards biological application, is demonstrated with the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. Cell imaging studies conducted with spectral mapping technique and confocal fluorescent microscopy demonstrate the YVO4:Eu NPs to be a type of competitive luminescent probes for in vitroapplications.

A film with a single-layer of size controlled silver nanocrystals embedded in silicon dioxide (SiO2) dielectric film by magnetic sputtering has been fabricated for nonvolatile memory applications. The effects of sputtering power, deposition time and substrate temperature on Ag nanocrystals formation were investigated. Transmission electron microscopy (TEM) images showed the as-prepared Ag nanocrystals had high uniformity in their size and distribution. The relationship between Ag nanocrystal size, density and electron storage capability as well as date retention time has been discussed.

Inoculating excess sludge was adopted by most wastewater treatment plants (WWTP). But inoculating excess sludge has these problems usually: high cost for buying, transportation and dosing number seeding sludge, and activated sludge having lag phase. Inoculating primary sludge is supposed a promising method. The total bacterial count of the influent and effluent was detected by DAPI (4′, 6-diamidino-2-phenylindole) staining in primary sedimentation. And the total bacterial count of the effluent was 9.7% of that in the influent on an average. Most of bacterial was settled with primary sludge. The comparative study has been done about the start-up of an activated sludge system by inoculating primary sludge and no primary sludge. The result showed that: at 20°C, in the system which was inoculated primary sludge, the mixed-liquor suspended solids (MLSS) was 2815mg/L, the ammonia nitrogen and Chemical Oxygen Demand(COD) in effluent were 0.65 mg/L and 47.6 mg/L respectively on the 9th day, so the start-up was succeed. Primary sludge is a kind of cheap seeding sludge, which can be obtained easily in WWTP, and the activated sludge system can be quick started up easily by inoculating primary sludge.

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