Experimental study of non-Newtonian fluid flow in microchannels

This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute.Non-Newtonian fluid flow in microchannels has significant applications in science and engineering. The effects of temperature and PAM solution concentrations on rheological parameters are analyzed by measuring them with rotating cylinder viscometer. Flow characteristics for deionized water and PAM solutions in fused silica microtubes with diameters ranging from 50 to 320μm, fused silica square microchannels with diameters 75 and 100μm, and stainless steel microtubes with diameters from 120 to 362μm, are studied experimentally. The test results for deionized water in microchannels are in good agreement with theoretical predictions for conventional-size channels. Friction factors of PAM solutions are much higher than theoretical predictions. With the PAM concentration reduced, the deviation is more, which is possibly caused by the significant electroviscous effect on PAM solutions flow in microchannels

Balancing the yin and yang: TMT gender diversity, psychological safety, and firm ambidextrous strategic orientation in Chinese high-tech SMEs

This paper offers a novel theoretical account of why and when top management team (TMT) gender diversity lends strategic advantage. Building on social role theory, we develop a moderated-mediation model showing: a) TMT psychological safety mediates the effect of TMT gender diversity on firm ambidextrous strategic orientation (ASO) (why) and b) firm slack moderates this mediated effect (when). We tested our model in the context of Chinese high-tech small- and medium-sized enterprises. After confirming gender differences in social role-based proclivities at the TMT level, a multi-wave survey study of 373 members from 120 TMTs showed that TMT gender diversity positively affects ASO via TMT psychological safety, and this mediated effect is stronger when firm slack is lower than higher. We further interviewed 23 top managers to supplement key quantitative results. Our study advances upper echelons research on TMT gender diversity in two ways. First, it highlights the gender-specific interpersonal benefit of TMT gender diversity, which is markedly distinct from the cognitive-variety argument associated generically with TMT demographic diversity. Second, it considers both men and women in TMTs in a more balanced manner, thereby offering an alternative account to the female-focused theorization of the positive strategic implications of TMT gender diversity

Spatial and temporal genetic heterogeneity of epidermal growth factor receptor gene status in a patient with non-small cell lung cancer: a case report

<p>Abstract</p> <p>Introduction</p> <p>To date, an epidermal growth factor receptor-activating mutation is recognized as a genetic hallmark that predicts a good response to treatment with epidermal growth factor receptor tyrosine kinase inhibitor. However, there has been less long-term observation of the mutational status within the same patient. To the best of our knowledge, this is the first case report which illustrates the instability of the genetic status of pulmonary adenocarcinoma cells.</p> <p>Case presentation</p> <p>A 64-year-old Japanese woman with advanced lung adenocarcinoma had been undergoing various anticancer treatments, including epidermal growth factor receptor tyrosine kinase inhibitor, for seven years. She had been receiving locoregional treatment in addition to systemic treatment. She maintained a good performance status until seven years after the initial diagnosis, although she had local and distant recurrences. We analyzed the genetic status of the epidermal growth factor receptor gene in a series of specimens obtained from various tumor-containing lesions throughout the therapeutic period. The results of the genetic analyses clearly showed that the spatial and temporal genetic heterogeneity of the epidermal growth factor receptor gene status originated from an identical tumor ancestor.</p> <p>Conclusions</p> <p>An alternative paradigm to determine a therapeutic strategy for a patient with lung cancer should be considered given the genetic heterogeneity and instability of tumor cells.</p

Two-Functional Direct Current Sputtered Silver-Containing Titanium Dioxide Thin Films

The article reports on structure, mechanical, optical, photocatalytic and biocidal properties of Ti–Ag–O films. The Ti–Ag–O films were reactively sputter-deposited from a composed Ti/Ag target at different partial pressures of oxygen on unheated glass substrate held on floating potentialUfl. It was found that addition of ~2 at.% of Ag into TiO2film has no negative influence on UV-induced hydrophilicity of TiO2film. Thick (~1,500 nm) TiO2/Ag films containing (200) anatase phase exhibit the best hydrophilicity with water droplet contact angle (WDCA) lower than 10° after UV irradiation for 20 min. Thick (~1,500 nm) TiO2/Ag films exhibited a better UV-induced hydrophilicity compared to that of thinner (~700 nm) TiO2/Ag films. Further it was found that hydrophilic TiO2/Ag films exhibit a strong biocidal effect under both the visible light and the UV irradiation with 100% killing efficiency ofEscherichia coliATCC 10536 after UV irradiation for 20 min. Reported results show that single layer of TiO2with Ag distributed in its whole volume exhibits, after UV irradiation, simultaneously two functions: (1) excellent hydrophilicity with WDCA < 10° and (2) strong power to killE. colieven under visible light due to direct toxicity of Ag

Fabrication of surface-patterned ZnO thin films using sol-gel methods and nanoimprint lithography

Surface-patterned ZnO thin films were fabricated by direct imprinting on ZnO sol and subsequent annealing process. The polymer-based ZnO sols were deposited on various substrates for the nanoimprint lithography and converted to surface-patterned ZnO gel films during the thermal curing nanoimprint process. Finally, crystalline ZnO films were obtained by subsequent annealing of the patterned ZnO gel films. The optical characterization indicates that the surface patterning of ZnO thin films can lead to an enhanced transmittance. Large-scale ZnO thin films with different patterns can be fabricated by various easy-made ordered templates using this combination of sol-gel and nanoimprint lithography techniques.Comment: 17 pages, 5 figures; Published in Journal of Sol-Gel Science and Technology, 201

Observation of a ppb mass threshoud enhancement in \psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p}) decay

The decay channel $\psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p})$ is studied using a sample of $1.06\times 10^8$ $\psi^\prime$ events collected by the BESIII experiment at BEPCII. A strong enhancement at threshold is observed in the $p\bar{p}$ invariant mass spectrum. The enhancement can be fit with an $S$-wave Breit-Wigner resonance function with a resulting peak mass of $M=1861^{+6}_{-13} {\rm (stat)}^{+7}_{-26} {\rm (syst)} {\rm MeV/}c^2$ and a narrow width that is $\Gamma<38 {\rm MeV/}c^2$ at the 90% confidence level. These results are consistent with published BESII results. These mass and width values do not match with those of any known meson resonance.Comment: 5 pages, 3 figures, submitted to Chinese Physics