This article reports on the International Nanofluid Property Benchmark Exercise, or INPBE, in which the thermal conductivity of identical samples of colloidally stable dispersions of nanoparticles or "nanofluids," was measured by over 30 organizations worldwide, using a variety of experimental approaches, including the transient hot wire method, steady-state methods, and optical methods. The nanofluids tested in the exercise were comprised of aqueous and nonaqueous basefluids, metal and metal oxide particles, near-spherical and elongated particles, at low and high particle concentrations. The data analysis reveals that the data from most organizations lie within a relatively narrow band ͑Ϯ10% or less͒ about the sample average with only few outliers. The thermal conductivity of the nanofluids was found to increase with particle concentration and aspect ratio, as expected from classical theory. There are ͑small͒ systematic differences in the absolute values of the nanofluid thermal conductivity among the various experimental approaches; however, such differences tend to disappear when the data are normalized to the measured thermal conductivity of the basefluid. The effective medium theory developed for dispersed particles by Maxwell in 1881 and recently generalized by Nan et al. ͓J. Appl. Phys. 81, 6692 ͑1997͔͒, was found to be in good agreement with the experimental data, suggesting that no anomalous enhancement of thermal conductivity was achieved in the nanofluids tested in this exercise.

This work reported an experimental investigation of complete oxidation of nickel nanoparticles using simultaneous thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC). Nickel nanoparticles and their elemental compositions were characterized by Brunauer-Emmett-Teller (BET) analysis, transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS). The oxidation experiments were performed under isoconversion conditions for seven heating rates, varying from 2 to 20 K min(-1), with temperatures up to 1000 degrees C. The experiments revealed unique oxidation behaviour of nickel at the nanometre scale, such as early oxidation and melting phenomena, variable activation energies and different oxidation kinetics between low and high conversion ratios. Unlike its bulk counterpart where the activation energy is a constant, the activation energy of nickel nanoparticles depended on the conversion ratio, ranging between 1.4 and 1.8 eV. The oxidation kinetics of nickel nanoparticles changed from the classical diffusion controlled mechanism to a pseudo-homogeneous reaction as conversion ratios were over 50%. The oxidation mechanisms of nickel nanoparticles were further discussed and future studies to enhance understanding were identified.

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Epithelial-mesenchymal transition (EMT) allows neoplastic cells to gain the invasive phenotype and become migratory, which is required for cancer progression and metastasis. In the present study, the expression of EMT-associated biomarkers and their association with clinicopathological parameters in laryngeal squamous cell carcinoma (LSCC) was investigated. E-cadherin, N-cadherin, β-catenin and zinc finger E-box binding homeobox 2 (ZEB2) protein expression was evaluated with immunohistochemistry in a cohort of 76 patients with operable LSCC. The association between these transition markers, clinicopathological parameters and their prognostic impact in LSCC was analyzed. Immunohistochemical analysis revealed that EMT-associated proteins were differentially expressed between LSCC and adjacent non-neoplastic laryngeal tissue. Negative E-cadherin expression and positive N-cadherin, β-catenin and ZEB2 expression were associated with a later tumor (T) stage, decreasing tumor differentiation and a reduced overall survival (OS) time (OS: E-cadherin, P=0.016; N-cadherin, P=0.003; β-catenin, P=0.002; ZEB2, P=0.0003). E-cadherin/β-catenin co-expression was significantly associated with the majority of clinicopathological parameters assessed, including lymph node metastases, T stage and tumor cell differentiation (P=0.004, P=0.005, and P<0.001, respectively). Multivariate analysis indicated that T stage and the positive expression of β-catenin and ZEB2 were independent risk factors for OS in LSCC (P=0.014, P=0.025 and P=0.003, respectively). It was concluded that EMT mediates tumor progression, and reduces OS time in patients with LSCC. E-cadherin/β-catenin co-expression may be associated with clinicopathological parameters. T stage, and the positive co-expression of β-catenin and ZEB2 may be independent predictors of prognosis in LSCC.

Tartary buckwheat is rich in flavonoids. However, the health‐promoting effect of these flavonoids has not been adequately studied. In the present study, we investigated the impact of rutin, quercetin, and Tartary buckwheat on the lipid metabolism of rats on a high‐fat diet. Quercetin could significantly reduce body weight, serum triacylglycerol, low‐density lipoprotein cholesterol, TNF‐α, insulin, and ameliorate glucose tolerance. It was surprising that Tartary buckwheat significantly increased the weight of the rats. Rutin, quercetin, and Tartary buckwheat tended to decreased fat deposition in the liver of rats but have little effect on short‐chain fatty acid production. The changes in the structure and diversity of the microbiota were found to be modulated by these diets. It was concluded that quercetin could attenuate high‐fat diet‐induced obesity, rutin, quercetin, and Tartary buckwheat can shape the specific structure of gut microbiota. Mechanism of Tartary buckwheat on lipid metabolism needs further systematic research.

The molecular mechanisms of acute lung injury (ALI) are closely associated with nucleotide-binding domains and leucine-rich repeat (NLR) pyrin domains containing 3 (NLRP3) inflammasome, in which alveolar macrophages (AMs) exert an essential function. Our study has been proved that artesunate (AS) inhibits ALI. Nevertheless, the inhibition actions of AS on activation of NLRP3 in renal ischemia-reperfusion (RIR)-mediated ALI remain to be further discussed. Male Sprague-Dawley rats were randomly assigned into four groups: sham + NS, sham + AS, RIR + NS, and RIR + AS. RIR-mediated ALI was performed through bilateral renal pedicle occlusion for 60 min followed by reperfusion for 24 h. AS (15 mg/kg) or NS was injected intraperitoneal to rat 1 h before RIR treatment. AMs were rendered hypoxic (0.5%) for 2 h and reoxygenated for 24 h. Lung injury index and histology, and inflammatory cells and cytokine release in the BALF and AMs were examined. The protein and mRNA levels of NLRP3, ASC, and caspase-1 in the lung and AMs were evaluated via Western blot and real-time RCR. In this research, we indicated that AS preconditioning inhibited RIR-mediated lung damage, vascular permeability, and edema in rats. AS reduced RIR-mediated ALI, as characterized by abatement in the count of inflammatory cells, and the production of inflammatory cytokines in the BALF. AS administration inhibited the number of F4/80-positive cells, the activity of myeloperoxidase, and the fiery cytokines mRNA expression in lung samples of RIR-stimulated rats. Furthermore, AS alleviated the activity of caspase-1 and activation of NLRP3 through depending on reactive oxygen species (ROS). An in vitro finding that AS mitigated hypoxia/reoxygenation-mediated activation of AMs partially supported in vivo study. In a word, these findings demonstrate that AS pretreatment attenuated RIR-mediated ALI potentially through reducing ROS-induced activation of the NLRP3 inflammasome.

BACKGROUND: Chemical looping combustion (CLC) is a promising environmentally friendly technology in which the greenhouse gas CO 2 can be readily separated at high-purity, therefore providing an effective method of carbon capture. Its performance, however, is limited by the kinetics of oxidation of the oxygen carrier, whose size is typically in the range of micrometers to millimetres. This paper reports a new idea using metallic nanoparticles as potential oxygen carriers to improve the performance of chemical looping combustion.

Oxidation of tin nanoparticles is studied in this paper using a simultaneous TGA/DSC technique under both constant rates of heating and isothermal modes. A two-stage oxidation process is identified. XRD study shows that the only oxide product is SnO at a temperature below 400 °C, and SnO and SnO 2 coexist at the temperature range between 400 and 900 °C. On the basis of the identified oxide constituent, the first-stage oxidation of tin nanoparticles is investigated by the model-free Kinssinger method. The activation energy is found to be dependent on the conversion ratio in a broad range of 0.32-1.33 eV, and the oxidation kinetics is identified to be the classical nucleation mechanism that can be modeled by the Avrami-Erofeev equation. The melting of tin and large pressure built up in a rigid oxide shell are believed to be responsible for the heterogeneous nucleation mechanism.