Nanoparticles are increasingly being recognized for their potential utility in biological applications including nanomedicine. Here we examine the response of normal human cells to ZnO nanoparticles under different signaling environments and compare it to the response of cancerous cells. ZnO nanoparticles exhibit a strong preferential ability to kill cancerous T cells (∼28-35×) compared to normal cells. Interestingly, the activation state of the cell contributes toward nanoparticle toxicity, as resting T cells display a relative resistance while cells stimulated through the T cell receptor and CD28 costimulatory pathway show greater toxicity in direct relation to the level of activation. Mechanisms of toxicity appear to involve the generation of reactive oxygen species, with cancerous T cells producing higher inducible levels than normal T cells. In addition, nanoparticles were found to induce apoptosis and the inhibition of reactive oxygen species was found to be protective against nanoparticle induced cell death. The novel findings of cell selective toxicity, towards potential disease causing cells, indicate a potential utility of ZnO nanoparticles in the treatment of cancer and/ or autoimmunity.

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The discrepancy between measured turbulence intensity obtained from experiments in wall bounded turbulence and the fully-resolved reference results (usually from DNS datasets) are often attributed to spatial resolution issues, especially in PIV measurements due to the presence of spatial averaging within the interrogation region/volume. In many cases, in particular at high Reynolds numbers (where there is a lack of DNS data), there is no attempt to verify that this is the case. There is a risk that attributing unexpected PIV statistics to spatial resolution, without careful checks, could mask wider problems with the experimental setup or test facility. Here we propose a robust technique to validate the under-resolved PIV obtained turbulenceintensity profiles for canonical wall-bounded turbulence. This validation scheme is independent of Reynolds number and does not rely on empirical functions. It is based on arguments that (i) the viscous-scaled small-scale turbulence energy is invariant with Reynolds number and that (ii) the spatially under-resolved measurement is sufficient to capture the large-scale energy. This then suggests that we can estimate the missing energy from volume-filtered DNS data at much lower Reynolds numbers. Good agreement is found between the experimental results and estimation profiles for all three velocity components, demonstrating that the estimation tool successfully computes the missing energy for given spatial resolutions over a wide range of Reynolds numbers. A database for a canonical turbulent boundary layer and associated MATLAB function are provided that enable this missing energy to be calculated across a

Turbulence modifications over a rough wall with spanwise-varying roughness are investigated at a moderate Reynolds number Reτ ≈ 2000 (or Reθ ≈ 6400), using particle image velocimetry (PIV) and hotwire anemometry. The rough wall is comprised of spanwise-alternating longitudinal sandpaper strips of two different roughness heights. The ratio of high- and low-roughness heights is 8, and the ratio of high- and low-roughness strip width is 0.5. PIV measurements are conducted in a wall-parallel plane located in the logarithmic region, while hotwire measurements are made throughout the entire boundary layer in a cross-stream plane. In a time-average sense, large-scale counter-rotating roll-modes are observed in the cross-stream plane over the rough wall, with downwash and upwash common-flows displayed over the high- and low-roughness strips, respectively. Meanwhile, elevated and reduced streamwise velocities occur over the high- and low-roughness strips, respectively. Significant modifications in the distributions of mean vorticities and Reynolds stresses are observed, exhibiting features of spatial preference. Furthermore, spatial correlations and conditional average analyses are performed to examine the alterations of turbulence structures over the rough wall, revealing that the time-invariant structures observed are resultant from the time-average process of instantaneous turbulent events that occur mostly and preferentially in space.

Currently, environmental issues are being discussed in various countries, including Indonesia. Erratic climate change greatly affects global warming worldwide, one of erratic climate change related to carbon emissions disclosures. However, there are still inconclusive findings regarding factors that determine the extent of carbon emissions disclosure. Based on comprehensive research, the objective of this paper is to examine a few selected factors and their relationship to the extent of carbon emissions disclosure. Green strategy, corporate social responsibility disclosure, good corporate governance, the board of directors, institutional ownership, and financial performance were analyzed to seek any significant relationships to the extent of carbon emissions disclosure. To this end, this study used a modified carbon emissions disclosure measurement from previous studies and a Corporate Social Responsibility Disclosure measurement using a combined corporate social responsibilitymatrix from three countries. Corporate annual reports from the consumer goods industry for the years 2015–2019 were examined to verify carbon emissions disclosure practices by applying content analysis and multiple regression analysis with a quantitative approach. The findings show that green strategy, Corporate Social Responsibility Disclosure, good corporate governance, and financial performance were found to have significant positive influences on the extent of carbon emissions disclosure. Meanwhile, the board of directors and institutional ownership had no significant influence on the extent of carbon emissions disclosure. This research can be used as a basis for developing an innovative strategy in environmental protection that can serve as a guideline for internal company regulations and public regulations to consider environmentally friendly products and services.