Application of microtechnology to elucidate nanotechnology

Engineereed nanoparticles (ENPs) are being used widely for their promising properties. In particular, zinc oxide (ZnO) and titanium dioxide (TiO2) nanoparticles (NPs) are two ENPs commonly found in sunscreen products for their UV absorbing properties. However, concerns have risen regarding the safety of their usage due to possible cytotoxic effects it may induce onto humans. Current methods in determining the cytotoxic levels of these ENPs utilises classic cell culture methods which presents limitations in presenting relevant in-vivo microenvironments. The dynamic complexity of in-situ microenvironment is not fully reflected and hence, there may be disparity in cellular functions and outcomes. By using micropatterning to assess cytotoxicity, an in-depth understanding of the mechanistic pathways of nanoparticles can be unveiled. Our study demonstrates using micropatterning as a tool in determining the cytotoxic effects of surface functionalised ZnO NPs and TiO2 NPs on human dermal keratinocytes (HaCaT cells). In our first study, with the aim of investigating how the cytotoxic response of ENPs is influenced by cell cluster size, circular islands of 50 um and 150 um in diameter were micropatterned before treatment with surface functionalised ZnO NPs. Our results have shown no difference in toxicity outcome though there are differences in mitochondria reactive oxygen species (mROS). This suggests that cellular functions may be impaired without causing cell death. In the second study, to examine how ENPs have an effect on cell chirality, circular islands of 150 um in diameter were treated with ZnO and TiO2 NPs. Our results have shown that ROS generation by both NPs led to an overall decrease in cell velocity, and possible differences in toxic pathway between the two NPs may have led to varying observations in directional sensing of the micropatterned cells.Bachelor of Engineering (Materials Engineering

The Impact of the Sociological Role of the Stakeholder on the Sustainability of the Economic Benefits of Cultural Heritage Transformation: the Cockatoo Island as an Example

Waterfront cultural heritage has unique historical, scientific, social and aesthetic values that can provide an excellent platform and starting point for urban design. The Cockatoo Island has significant differences in these values, which make it complex and contradictory in the subsequent tourism-oriented transformation, and even create a certain value mismatch. Combined with its rich history of colonialism, prisoner history, social class and other complex issues, as well as its recent financial crisis, it is a worthy case study. This paper analyzes the factors affecting the sustainability of the economic reproduction of the Cockatoo Island at the political stakeholder level and the related sociological level to explore the relationship between government involvement and the properties of cultural heritage itself.AR2A011Architectural History ThesisArchitecture, Urbanism and Building Science

Fruit, seed and embryo development of different cassava (Manihot esculenta Crantz) genotypes and embryo rescue

Fruit, seed and embryo developments of different cassava (Manihot esculenta Crantz) genotypes, as well as embryo rescue, were investigated. The fruits of three genotypes after uncontrolled open pollination presented the same progressive development with similar sizes at different stages. There are large differences in the fruit set as well as the embryo development between different genotypes. Days after pollination (DAP) was found not to be an adequate predictor of embryo size as their size ranged from almost invisible to 8.7 mm in length at 32 DAP even within the different locules of the same fruit. The ideal stage for embryo rescue in cassava was from 32 to 36 DAP, because at that stage most embryos are visible (> 0.7 mm); and their excision without injury is feasible. Also, in vitro germination of the cotyledonary embryos at that stage had a high success rate. A half Murashige and Skoog (MS) medium supplemented with 1.0 mg/l GA3, 2% sucrose and 0.2% gel rite proved to be adequate for embryo rescue.Keywords: Manihot esculenta Crantz, day after pollination (DAP), fruit set, seed size, embryo size, embryo rescueAfrican Journal of Biotechnology, Vol 13(14), 1524-152

Direct Denial or Positive-Negative Rumor Rebuttal? The Effects of Two Types of Rumor Rebuttal and Their Psychological Mechanisms

This study used a single-factor online experiment to explore&nbsp;the&nbsp;effect&nbsp;of&nbsp;the&nbsp;presentation&nbsp;of&nbsp;rumor&nbsp;rebuttal&nbsp;information (direct&nbsp;rebuttal&nbsp;vs. positive-negative&nbsp;rebuttal) on&nbsp;rumor&nbsp;credibility, and&nbsp;the&nbsp;role&nbsp;of&nbsp;emotion and depth&nbsp;of&nbsp;information processing in this process.&nbsp;The&nbsp;findings revealed that&nbsp;direct&nbsp;rebuttal&nbsp;significantly reduced&nbsp;rumor&nbsp;credibility to subjects when compared to no&nbsp;rebuttal, while no significant&nbsp;effect&nbsp;was found in positive-negative&nbsp;rebuttal. In addition, positive emotions, negative emotions, and&nbsp;the&nbsp;depth&nbsp;of&nbsp;information processing triggered by&nbsp;rumors&nbsp;partially mediated&nbsp;the&nbsp;effect&nbsp;of&nbsp;direct&nbsp;rebuttal&nbsp;on&nbsp;rumor&nbsp;credibility. This suggests that&nbsp;the&nbsp;method&nbsp;of&nbsp;rebuttal&nbsp;can significantly influence people&#39;s perceptions&nbsp;of&nbsp;rumors, and that&nbsp;direct&nbsp;denial&nbsp;may be more&nbsp;effective&nbsp;than&nbsp;rebuttal&nbsp;through detailed explanations containing both positive and negative information, which is practically valuable for&nbsp;effective&nbsp;rebuttals&nbsp;in social governance.</p

Identification and Expression Analysis of Gretchen Hagen 3 (GH3) in Kiwifruit (Actinidia chinensis) During Postharvest Process

In plants, the Gretchen GH3 (GH3) protein is involved in free auxin (IAA) and amino acid conjugation, thus controlling auxin homeostasis. To date, many GH3 gene families have been identified from different plant species. However, the GH3 gene family in kiwifruit (Actinidia chinensis) has not been reported. In this study, 12 AcGH3 genes were identified, phylogenetic analysis of AtGH3 (Arabidopsis), SlGH3 (Solanum lycopersicum), and AcGH3 provided insights into various orthologous relationships among these proteins, which were categorized into three groups. Expression analysis of AcGH3 genes at different postharvest stages suggested limited or no role for most of the AcGH3 genes at the initiation of fruit ripening. AcGH3.1 was the only gene exhibiting ripening-associated expression. Further study showed that the expression of AcGH3.1 gene was induced by NAA (1-naphthylacetic acid, auxin analogue) and inhibited by 1-MCP (1-methylcyclopropene, ethylene receptor inhibitor), respectively. AcGH3.1 gene silencing inhibited gene expression and delayed fruit softening in kiwifruit. The results indicate that AcGH3.1 may play an important role in the softening process of fruits. Analysis of the AcGH3.1 promoter revealed the presence of many cis-elements related to hormones, light, and drought. The determination of GUS (&beta;-Galactosidase) enzyme activity revealed that promoter activity increased strikingly upon abscisic acid (ABA), ethylene, or NAA treatment, and significantly decreased with salicylic acid (SA) treatment. The present study could help in the identification of GH3 genes and revelation of AcGH3.1 gene function during postharvest stages, which pave the way for further functional verification of the AcGH3.1 gene

Modified P&O Approach Based Detection of the Optimal Power-Speed Curve for MPPT of Wind Turbines

Improving operation efficiency has gained attention for wind turbine operation and maintenance. This chapter proposes a method to dynamically calibrate the optimal power-speed curve (OPSC) based on a modified perturbation and observation (P&O) approach to improve power signal feedback (PSF) based maximum power point tracking (MPPT). The detection takes advantage of the P&O approach without detailed modelling. By controlling the wind turbine rotational speed and recording operating data, the maximum power points (MPPs) can be calculated. The OPSC is obtained from the calculated MPPs and applied in PSF control to improve the MPPT efficiency. Simulation and experimental results show that this method can effectively obtain the OPSC for wind turbines to achieve MPPT

Ego-Resiliency and Perceived Social Support in Late Childhood: A Latent Growth Modeling Approach

This study explored the change trajectory of schoolchildren’s ego-resiliency and perceived social support and investigated the effect of perceived social support on ego-resiliency across four time points. A sample of 437 children aged 8–13 years (M = 10.99, SD = 0.70, 51.5% boys) completed assessments at four time points. The results indicated that ego-resiliency showed an increasing linear trend and perceived social support showed a declining linear trend. Perceived social support had a positive effect on ego-resiliency over time. In addition, the initial status of perceived social support negatively predicted the growth trend of ego-resiliency, and the initial status of ego-resiliency negatively predicted the declining trend of perceived social support. The implications for theory and practice are discussed

Adsorption Thermodynamics and Dynamics of Three Typical Dyes onto Bio-adsorbent Spent Substrate of <i>Pleurotus eryngii</i>

Dyeing wastewater is very hard to treat, and adsorption could be a good choice. Spent substrate of Pleurotus eryngii (SSPE) was first used to adsorb malachite green, safranine T and methylene blue from aqueous solutions, and the corresponding adsorption isotherm, thermodynamics and dynamics models were simulated. More than 93% of the dyes were removed with solutions with 100 mg/L of initial dye concentration, 1 g of SSPE and pH of 6.0 after adsorption for 4 h. Freundlich isotherm models fit better the adsorption data than Langmuir models. Adsorption of the dyes onto SSPE was a spontaneous exothermic process based on an adsorption thermodynamics model. SSPE could adsorb the dyes rapidly, and a second-order kinetics model fit better with the adsorption data than a pseudo first-order kinetics model. Accordingly, SSPE could be a good bio-adsorbent for the removal of malachite green, safranine T and methylene blue from the aqueous solution

The Effects on the Cutting Propagation of Cinnamomum micranthum in Different Seasons

Cinnamomum micranthum is one of China Third-class Endangered Tree Species. The seedlings of C. micranthum are difficult to obtain. It is important to study the cutting propagation of C. micranthum in different seasons to improve the rooting rate for providing seedling propagation technique for the afforestation industry. In this study, the optimal season for the cutting propagation of C. micranthum was summer (May), providing 80.6% rooting rate. The rooting rate in Summer was 33.4% higher than that in Spring (March). This technique is important to make the best use of rare C. micranthum resources and to provide plenty of seedlings for afforestation and greening industry