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The Sichuan–Yunnan–Guizhou (SYG) Pb–Zn mineral province, which has significant Pb–Zn repositories in China, is situated in the western Yangtze Block. Despite decades of research, the Pb–Zn source of deposits is still disputed between the basement rocks, sedimentary wall rocks, or the Emeishan flood basalts. The newly-discovered Laoxiongdong Pb–Zn deposit is hosted by the Late Ediacaran Dengying Formation in the SYG province. Moreover, the Laoxiongdong orebodies lie between regional deep faults and close to the Proterozoic basement and Emeishan basalts. Hence, this deposit represents a good case study on the ore-forming material source for the regional Pb–Zn mineralization. The Laoxiongdong Pb–Zn ores are massive, vein, or disseminated and have mainly sphalerite, galena, pyrite, quartz, and calcite. In this paper, we present new sulfide S–Pb–Zn isotope data of the deposit. The sulfide δ34SCDT values (+ 11.8 to + 16.5 ‰) suggest that the reduced sulfur was mainly sourced from evaporites in the Late Ediacaran–Cambrian sequences. Pb isotopic ratios (206Pb/204Pb = 18.004–18.107, 207Pb/204Pb = 15.652–15.667, and 208Pb/204Pb = 38.037–38.248) suggest that the lead metal was primarily originated from the basement rocks. The sphalerite δ66Zn values (+ 0.16 to + 0.37 ‰) are also highly similar (within error) to those of basement rocks (+ 0.10 to + 0.34 ‰), suggesting a basement-rocks zinc source with minor contributions from the carbonate host rocks and Emeishan flood basalts. The narrow sphalerite Zn isotopic range (0.21 ‰) also indicates that the Zn isotopic fractionation between the sphalerite and initial fluid was limited during the sphalerite ore precipitation. Therefore, we propose that both the Late Ediacaran Dengying Formation rocks and Proterozoic basement rocks were important ore-forming material source for the Laoxiongdong deposit, whereas the Emeishan flood basalts represent only a minor ore-material source.

The aim of this paper is to find an effective way to reduce the friction and wear of steel. CrCN coating was deposited on AISI 304 stainless steel by magnetron sputtering technology, and the friction and wear properties of the coating under glycerol lubrication were studied. The hardness of CrCN coatings on stainless steel surface can reach to 17.87 GPa when the carbon target deposition current is 2A. The CrCN coating presents low friction coefficient (COF) under the lubrication of glycerol, a highly efficient green lubricant. When the load is 0.5 N, the lowest friction coefficient is only 0.01. XPS analysis on the wear track suggested that glycerol decomposed during sliding and a fluid lubricating layer was formed, which provides ultralow friction. The paper shows that the glycerol could be used as an efficient lubricant for the CrCN coating.

Gamma-glutamylcyclotransferase (GGCT) can promote the progression of osteosarcoma (OS). MicroRNAs also play significant roles in regulating the progression of OS. This study was designed to investigate whether miR-877 exerts its function in OS by targeting GGCT. The proliferation of OS cells (Saos-2 and U2OS) was detected by MTT and colony formation assays. The migration and invasion of OS cells were detected by transwell assays. The expressions of miRNAs and GGCT were detected by quantitative real-time PCR and Western blot. The luciferase reporter assay was performed to assess whether miR-877 could target GGCT. miR-877 was down-regulated both in OS tissues and OS cell lines (Saos-2 and U2OS). The overexpression of miR-877 inhibited the proliferation, migration, and invasion of OS cell lines, while the knockdown of miR-877 could negate effects. The expression of GGCT was increased in Saos-2 and U2OS cells. miR-877 could target GGCT, and the mRNA level of GGCT in Saos-2 and U2OS cells was decreased by the overexpression of miR-877. miR-877 overexpression inhibited the migration and invasion and suppressed the proliferation of Saos-2 and U2OS cells, and the overexpression of GGCT reversed this effects. The knockdown of miR-877 promoted the migration and invasion and facilitated the proliferation of Saos-2 and U2OS cells, and the silence of GGCT abolished this effects. Our findings suggested that miR-877 could inhibit the proliferation, migration, and invasion of OS cells by targeting GGCT.

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BACKGROUND Allyl isothiocyanate (AITC), a classic anti-inflammatory and antitumorigenic agent, was recently identified as a potential treatment for obesity and insulin resistance. However, little is known about its direct impact on the liver.

Cytochrome P450 3A (CYP3A) activity is inhibited, and its expression is suppressed during many diseases, including nonalcoholic fatty liver disease (NAFLD). However, the mechanism is controversial. Here, we report that PXR may not take part in the downregulation of CYP3A during NAFLD. Hepatic CYP3A11 (major subtype of mouse CYP3A) mRNA and protein expression was significantly decreased in both mice fed a high-fat diet (HFD) for 8 weeks and palmitate (PA)-treated mouse primary hepatocytes. Similarly, in HepG2 cells, PA treatment significantly suppressed the CYP3A4 (major subtype of human CYP3A) mRNA level and promoter transcription activity. However, Western blotting analysis found an induction of PXR nuclear translocation during NAFLD in both in vivo and in vitro models. Moreover, immunofluorescence determination also found nuclear translocation effect of PXR by PA stimulation in HepG2 cells. In addition, the siRNA knockdown of PXR did not affect the suppressive effects of PA on the CYP3A4 promoter transcription activity and mRNA levels in HepG2 cells. Similarly, PXR knockdown also did not affect the suppressive effects of PA on CYP3A11 mRNA and protein expression levels in mouse primary hepatoctyes. Taken together, the results showed that the suppressive effect of CYP3A transcription was independent of PXR regulation.

The purpose of this paper is to evaluate carbon spheres as a green lubricant additive in 5W30 engine oil to reduce friction and wear. Carbon spheres with a diameter of ∼400 nm are synthesized from ...

As a carbonate-hosted deposit, the Huamuqing Pb–Zn deposit is situated in the western margin of the Yangtze Block. The strata-bound, irregular or vein-type Pb–Zn orebodies of the Huamuqing Pb–Zn deposit are mainly hosted by carbonate rocks of the Sinian Dengying Formation or Cambrian Meishucun Formation. Ores metallic minerals include mainly sphalerite, galena, and pyrite, whereas non-metallic minerals include mainly quartz and calcite. The alteration/mineralization can be divided into three stages: (I) the pyrite-quartz stage, (II) the polymetallic sulfide-quartz stage, and (III) the pyrite-calcite stage. The C–O isotopes of stage III hydrothermal calcite and multi-isotopes (S, Pb, Rb, Sr) of stage II sulfides were analyzed to constrain the ore-forming material source and mineralization timing at Huamuqing. The ranges of δ13CPDB and δ18OSMOW values for the stage III calcites are from − 0.641 to + 0.180‰ and + 17.542 to + 18.443‰, respectively. This suggests that the carbon of stage III was mainly derived from the Sinian dolostone, and the O isotope signatures of stage III were probably in connection with water/rock (W/R) interactions between the δ18O-depleted fluids and δ18O-enriched Sinian dolostone. The stage II sulfide δ34SCDT values vary from + 13.037 to +20.696‰, indicating that the reduced sulfur was originated mainly from Sinian to Triassic evaporites. The stage II sulfide 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ranges are from 18.184 to 18.393, 15.575 to 15.691, and 38.325 to 38.436, respectively. This demonstrates multiple Pb sources, which may have included sedimentary rocks, basement rocks, and basalts. Initial 87Sr/86Sr ratios of eight sphalerite samples range from 0.70815 to 0.71399, indicating that the ore fluids most probably came from or percolated through basement rocks, basalts, and sedimentary rocks. The mineralization timing was sphalerite Rb–Sr dated to be Late Triassic (204 ± 2 Ma), reflecting the Huamuqing deposit formed during late Indosinian. Hence, the Huamuqing deposit is a carbonate-hosted, thrust fault–controlled epigenetic Pb-Zn deposit that has a mixed source of ore-forming metals and ore-forming fluids.

Purpose The purpose of this paper is to increase wear resistance of aluminum. Design/methodology/approach The authors have studied the ways to improve the tribological performance of aluminum by assembling stearic acid on aluminum coated by sol-gel-derived TiO2 film. The samples were characterized by infrared spectroscopy, contact angle measurements and a macro friction and wear tester. Findings Enhanced wear resistance was clearly obtained after functionalization of TiO2 film on aluminum by stearic acid. Originality/value The relevant results might be helpful for guiding the surface modification of aluminum devices in industrial applications.

Titanium alloy shows a poor tribological performance even under lubrication. In this paper, we report the formation of carbon-based tribofilms from poly-alpha-olefin (PAO) base oil molecules on Ti6Al4V (Ti64) samples after thermal oxidization treatment, where PAO enabling base oils to provide not only the fluid but also the solid tribofilm. Ball-on-disk tests at contact pressures of 2.0 GPa reveal that these carbon-based tribofilms on thermally oxidized Ti64 samples decrease the friction coefficient by about 3 times and wear rate by up to 2 orders magnitude as comparing to untreated one.

Purpose The purpose of this paper is to evaluate naturally occurring phytic acid (PA) as a green-water-based lubricant. Design/methodology/approach Lubrication is studied using a ball-on-disk tribometer with silica glass against silicon nitride contact, and the friction coefficient and wear are measured in the boundary lubrication regimes. Findings Excellent lubrication performance was found by using PA aqueous solutions. After the running-in process, the sliding coefficient of friction could drop to as low as 0.01 with a quite low concentration of 7.5 × 10−4 M. The lubricating performance of PA solution could be further improved by increasing PA concentration. The work suggests that the excellent lubricity of PA in aqueous solution can be mostly contributed to its adsorption on the silica surface. Originality/value The paper shows that the natural products could be used as water-based lubricant additives.

Water can be used as an ecological lubricant base if the water-based additives are properly developed to modify its tribological properties. Additionally, those additives should be friend both to human and nature. Pullulan is a naturally occurring polysaccharide, which is biodegradable and non-toxic and widely used in food and nonfood applications. We focus here on understanding the lubrication properties of pullulan, in aqueous solution in absence and presence of sodium salts. Lubrication is studied using a ball-on-disk tribometer with steel–steel surfaces and the friction coefficient and wear are measured in the boundary lubrication regimes. The adsorption of pullulan molecules onto steel surface is determined by measuring wettability of friction couples. It was found that the addition of pullulan improves the lubricating properties of water. The lubricating performance of Pullulan solution could be further improved if sodium chloride or sodium fluoride is added. The tribological results obtaine...

Two-dimensional (2D) monolayer cell cultures are the most common in vitro models for mechanistic studies on the toxicity of engineered nanoparticles (NPs). However, 2D cell cultures may not accurately model the functions of three-dimensional (3D) tissues that have extensive cell–cell and cell–matrix interactions, and thus may lead to wrong experimental results. Hence, to obtain more adequate and detailed information about ZnO NP–tissue interactions, we here assess the toxicity and inflammatory effects of different-sized ZnO NPs at various concentrations on Caco-2 cells which are three-dimensionally cultured in agarose gels, measuring ROS expression, pro-inflammatory cytokines, cell proliferation and death. The results showed that the significant effects of cell dimensionality to cellular responses such as inflammatory response, cytotoxicity and different modes of cell death in response to ZnO NPs treatment. Moreover, ZnO NPs induced the toxicity of 2D and 3D cells in different size-dependent manners. This study revealed that the nanotoxicity conclusions obtained from the 2D cell model might overestimate the toxic effects of ZnO NPs. There is a more realistic mechanism study of nanoparticle-induced toxicity in the 3D cell model, which acts as an intermediate stage bridging in vitro 2D and in vivo models.

Electroless nickel boron (Ni-B) coatings are finding their applications in the aerospace, automotive, chemical and electrical industries due to their properties such as high hardness and high wear resistance. However, Ni-B coatings generally show high friction. They also suffered from severe attacks in aqueous solution containing Cl− ion. In this paper, the experiments are carried out to reduce the friction and improve corrosion resistant properties of Ni-B coating by PTFE impregnation. It is found that Ni-B coating after impregnated by an aqueous solution containing 40 wt% PTFE nanoparticles is able to withstand a rubbing test duration of 3600 s with the coefficient of friction as low as

Combination of chemotherapy and small interfering RNA (siRNA)-based nanotherapeutics could cooperatively and effectively suppress multiple drug resistance in cancer development. Particularly, nano-...

The superhydrophobic surface on copper is fabricated by using a simple hydrothermal reaction and subsequent perfluorosilane treatment. The micro-structured and nano-structured surface was directly obtained through the hydrothermal reaction of copper sheets with sulfur at 180 °C for 12 h, resulting in the formation of copper sulfide film on the copper substrate. The chemical composition of this film was confirmed using X-ray photoelectron spectroscopy. After copper sulfide film is treated by perfluorosilane, the superhydrophobic surface with static water contact angle of 153 °C and a low contact angle hysteresis is achieved. The superhydrophobic surface shows strong mechanical stability and can effectively protect the copper substrate. Copyright © 2016 John Wiley & Sons, Ltd.

Polyethylene terephthalate (PET) is a crystalline polymer with a high melting temperature (Tm) and glass transition temperature (Tg). Because of its good barrier properties, it is widely used in food, chemical, pharmaceutical packaging, electronics and many other fields. But due to the large number of ester bonds in the main chain of PET macromolecules, it is easily degraded by strong acids, bases and water vapor, and lead to the decrease of physical and mechanical properties. In this paper, PET was immersed in three different solutions (water, sulfuric acid, sodium chloride) to accelerate the aging. Combining with the mechanical properties test, the change of mechanical properties of PET before and after solution aging was studied to provide reference for improving the aging properties of PET. The results show that the tensile strength of PET increased by 12.7MPa, the flexural strength increased by 18.8MPa, the elongation at break decreased from 290% to zero with the aging time of solution, and the change of notched impact strength and hardness was not significant.

Polyethylene terephthalate (PET) is widely used in food and pharmaceutical packaging. In the processing, storage and use of the process, it will inevitably be in contact with air at a certain temperature, resulting in thermal-oxidative aging. So in this paper, the hot air exposure test was used to investigate the changes of structure before and after thermal-oxidative aging of PET by means of FTIR, DSC, UV-visible spectroscopy and fluorescence spectroscopy. IR study found that, after thermal-oxidative aging, the trans conformation of PET increased, the cis content decreased, and the carboxyl content of PET increased slightly. DSC analysis showed that the melting temperature, crystallization temperature and crystallinity of PET increased after thermal-oxidative aging. The results of IR, UV/Vis and fluorescence spectra showed that the crystallinity of PET increased after thermal-oxidative aging, the color difference (C) and the transparency (T%) increased, the yellow index(YI) decreased and the content of trans conformation was higher.

It is widely accepted that substantial nighttime sap flux (J s,n) or transpiration (E) occurs in most plants, but the physiological implications are poorly known. It has been hypothesized that J s,n or E serves to enhance nitrogen uptake or deliver oxygen; however, no clear evidence is currently available. In this study, sap flux (J s) in Eucalyptus grandis × urophylla with apparent stem photosynthesis was measured, including control trees which were covered by aluminum foil (approximately 1/3 of tree height) to block stem photosynthesis. We hypothesized that the nighttime water flux would be suppressed in trees with lower stem photosynthesis. The results showed that the green tissue degraded after 3 months, demonstrating a decrease in stem photosynthesis. The daytime J s decreased by 21.47%, while J s,n decreased by 12.03% in covered trees as compared to that of control, and the difference was statistically significant (P < 0.01). The linear quantile regression model showed that J s,n decreased for a given daytime transpiration water loss, indicating that J s,n was suppressed by lower stem photosynthesis in covered trees. Predawn (ψ pd) of covered trees was marginally higher than that of control while lower at predawn stomatal conductance (g s), indicating a suppressed water flux in covered trees. There was no difference in leaf carbon content and δ(13)C between the two groups, while leaf nitrogen content and δ(15)N were significantly higher in covered trees than that of the control (P < 0.05), indicating that J s,n was not used for nitrogen uptake. These results suggest that J s,n may act as an oxygen pathway since green tissue has a higher respiration or oxygen demand than non-green tissue. Thus, this study demonstrated the physiological implications of J s,n and the possible benefits of nighttime water use or E by the tree.

A novel 96-well liquid-liquid microextraction system combined with modern HPLC was developed and used for the simultaneous analysis of 96 biological samples. The system made use of hollow fibers, a 96-well plate, and a plastic base with a center hole and a side hole. One end of the hollow fiber was sealed, while the other end was attached to one of the holes positioned at the center for the plastic base. The needle was inserted into the liquid from inside or outside of the hollow fiber through the center or the side holes, respectively. The system was tested with plasma samples containing three compounds, acidic indomethacin, neutral dexamethasone, and basic propafenone. Some parameters, such as the kind and dimension of hollow fiber, pH and salt concentration of the donor phase, the selection of organic solvent for the acceptor phase, and the extraction time were investigated. Under the optimization conditions, the Log D and drug concentration of indomethacin, dexamethasone, and propafenone in plasma and urine samples were analyzed. Then, the methodology was validated. The results demonstrated that ng/mL levels could be exactly and rapidly analyzed by our system, which was equipped with an auto-injection sampler, making sample analysis more convenient.

The physiological and ecological responses of Ulmus elongata to different concentrations of nano-anatase TiO2 solutions were investigated in this study and we found that with foliar application of 0.1% (T1), 0.2% (T2) and 0.4% (T3) nano-anatase TiO2 solution the net photosynthetic rate of U. elongata seedlings were lower, comparing with the control (CK) (no spraying). TiO2 solution had no effect on the carbon isotope values (δ(13)C), indicating the lower photosynthetic capacity was not caused by stomatal limitation. The nitrogen isotope values (δ(15)N) decreased, but the foliar metal elements, such as Mg, K and Mn contents were not affected by nano-anatase TiO2 which promoted the Cu uptake. Fourier transform infrared spectroscopy showed that the nano-anatase TiO2 enhanced the absorbance of U. elongata leaves, especially for 1064, 1638, 2926 and 3386 cm(-1) bands, indicating the synthesis of carbohydrate and lipid compounds was a kind of mechanism under the toxic effects of nanonanoparticles.

A novel and reliable ion chromatography (IC) method using graphene (G) as a solid phase extraction (SPE) adsorbent for the rapid analysis of bisphenol A (BPA) in dairy products was developed. The performances of graphene (G) and commercial C18 for BPA extraction from dairy samples were evaluated; results showed that G had higher adsorption efficiency. IC coupled with an electrochemical detector (ED) is eco-friendly, labor and time saving compared to liquid chromatography mass spectrometry (LC-MS) and gas chromatography mass spectrometry (GC-MS). The effects of the experimental parameters of the IC-ED system were assessed, and the parameters were optimized to provide maximum sensitivity. The linear range is 5–20,000 ng mL−1 with an R value of 0.999. The limit of the detection is 0.8 ng mL−1 for a 25-μL injection loop. The mean relative recoveries ranged between 83.3 % and 104.6 %, the corresponding inter-day precision was below 5.3 % for 20, 200, 2,000, and 15,000 ng mL−1. This method was successfully employed to analyze BPA in dairy samples.

A simple two-step process was developed to render the low-friction copper surface with longer durability. The copper substrate was firstly etched by immersing it in H2O2/HCl solution to fabricate a CuCl film, while a layer of stearic acid was then deposited on the CuCl film. Scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared microscopy and water contact angle measurements were used to analyze the morphological features, the chemical composition and hydrophobicity of freshly prepared specimens, respectively. Moreover, the friction-reducing behavior of the dual-modified copper surface sliding against a steel ball under unlubricating condition was evaluated in tribotester with a ball-on-plate configuration. It is found that the tribological performances of copper substrate are much improved by depositing stearic acid films on the etched copper.

The main purpose of this study was to optimize the preparation of lysozyme nanoliposomes using response surface methodology and measure their stability. The stabilities of lysozyme nanoliposomes in simulated gastrointestinal fluid (SGF), simulated intestinal fluid (SIF), as well as pH, temperature and sonication treatment time were evaluated. Reverse-phase evaporation method is an easy, speedy, and beneficial approach for nanoliposomes’ preparation and optimization. The optimal preparative conditions were as follows: phosphatidylcholine-to-cholesterol ratio of 3.86, lysozyme concentration of 1.96 mg/mL, magnetic stirring time of 40.61 min, and ultrasound time of 14.15 min. At the optimal point, encapsulation efficiency and particle size were found to be 75.36% ± 3.20% and 245.6 nm ± 5.2 nm, respectively. The lysozyme nanoliposomes demonstrated certain stability in SGF and SIF at a temperature of 37 °C for 4 h, and short sonication handling times were required to attain nano-scaled liposomes. Under conditions of high temperature, acidity and alkalinity, lysozyme nanoliposomes are unstable.

A highly sensitive method using ultra-fast liquid chromatography coupled with quadrupole/linear ion trap mass spectrometry (UFLC-Q/Trap MS) was developed to simultaneously screen and confirm nine beta-blockers (BBs) in porcine tissues (porcine muscle, liver and kidney). The method was used for trace determination of atenolol, pindolol, acebutolol, metoprolol, carazolol, labetalol, bisoprolol, propranolol and penbutolol. The homogenized tissues were hydrolyzed by beta-glucuronidase/aryl sulfatase and extracted with acetonitrile, followed by continuous purification procedures of disperse solid phase extraction (d-SPE) with diatomaceous earth and BondElut cartridge. The ultra-fast chromatographic separation was conducted on a Kinetex C18-XB column (150 mm x 2.1 mm, 2.6 microm) using 0.1% (v/v) formic acid aqueous solution and methanol as mobile phases in gradient elution. The optimized ion transitions were mployed in the mixed-mode of scheduled multiple reaction monitoring (sMRM) -information dependent acquisition (IDA)-enhanced product ion (EPI) scan. Qualification analysis was performed through spectra-matching with on-line lab-built MS/MS library. For quantification stable isotope-labelled analogues of the analytes were used as internal standards. As a result, in porcine liver, kidney and muscle, the nine BBs showed good linearity with all the correlation coefficients (r) more than 0.995 in the range of 0.1-20 microg/L. The limits of quantification (LOQ, S/N > or = 10) were 0.5 kg/kg for all the analytes. The developed method gave average recoveries of 87.5%-111.8% spiked at 0.5, 1.0 and 5.0 microg/kg with the relative standard deviations of 4.0%-12. 5%. The proposed method can be used to screen and confirm the nine BBs in a single run, which makes it effective in surveillance and detection of the BBs residues in porcine tissues.