Gold-nanorod-facilitated nonlinear optical microscopy under radially polarised beam illumination

Reports on the use of radially polarised beam in gold-nanorod-facilitated nonlinear microscopy and therapy. It has been found that the use of radially polarised beam can greatly reduce the energy fluence threshold for treating cancer cells labelled with gold nanorods. The slight distortion in the polarisation properties of the radially polarised beam after propagating through double-clad photonic crystal fibres makes it promising in the application of fibre-optic based endoscopic system.

Two-photon imaging and photothermal therapy of cancer cells using biofunctional gold nanorods

Transferrin-conjugated gold nanorods were used for targeting, two-photon imaging and photothermal therapy of cancer cells. The presence of nanorods significantly reduced the laser power effective for therapy.

Gold nanoparticle-enhanced cancer photothermal therapy

In this paper, progress on the gold-nanoparticleenhanced photothermal therapy is reviewed. Size- and shapedependent optical absorption of gold nanoparticles, the effects of various parameters on the therapeutic efficiency, and the mechanisms of gold-nanoparticle-assisted cancer therapy are discussed. Future research directions of gold-nanoparticle-assisted cancer photothermal therapy are also suggested.

Photothermally induced apoptosis of cancer cells using gold nanorods for low energy cancer therapy

Gold nanorods functionalised with transferrin were used for photothermally induced necrosis and apoptosis of cancer cells. It was observed that the laser energy required to induce cell apoptosis is significantly lower than that for cell necrosis, indicating that photothermally induced apoptosis can be used for medically safe laser cancer treatment.

Enhanced photothermal therapy assisted with gold nanorods using a radially polarized beam

We report on the use of a radially polarized beam for photothermal therapy of cancer cells labeled with gold nanorods. Due to a three-dimensionally distributed electromagnetic field in the focal volume, the radially polarized beam is proven to be a highly efficient laser mode to excite gold nanorods randomly oriented in cancer cells. As a result, the energy fluence for effective cancer cell damage is reduced to one fifth of that required for a linearly polarized beam, which is only 9.3% of the medical safety level.

Self-assembly of gold nanowires along carbon nanotubes for ultrahigh-aspect-ratio hybrids

We report a novel approach for the assembly of one-dimensional hybrid nanostructures that consist of gold nanowires with ultrahigh aspect ratios (L/d > 500) self-assembled along the axes of multiwalled carbon nanotubes. The micrometer-long hybrid nanowires exhibit high electrical conductivity and can be easily microcontact-printed onto various substrates in a patterned form, suggesting that these hybrids have considerable potential as interconnects for nanoelectronic applications.

An exploration of the motivation to attend for spectators of the Lexmark Indy 300 champ car event, Gold Coast

The perceptions of spectators (N = 36) at the Lexmark Indy 300 Champ Car event were assessed via qualitative methods to evaluate their internal and external motivations to attend. The most common reason to attend was the atmosphere that the event created, and entertainment. Other reasons included the race, enjoying the company of friends, and group affiliation. The characteristics of the majority of attendees were predominantly male, 26 to 35 years old, from Queensland, who earned around AUD$50,000 to $75,000 per annum. The findings of the study have implications for sport marketers who wish to communicate to these individuals.

An examination of Australian gold mining firms' exposure over the collapse of gold price in the late 1990s

Purpose – The purpose of this study is to examine the exposures of Australian gold mining firms in the highly volatile period from 1995 to 2000. This period has been characterized by significant changes in gold price due to bulk sale of gold by collective central banks. Specifically, the paper aims to investigate several firm-specific factors that are hypothesized to carry substantial influence on gold beta.

Design/methodology/approach – To estimate gold beta, we use the following multifactor model: R_g,_t = a+ß_gGPR_t + ß_xFXR_t + ß_mR_m,_t + _Et , where R_g,_t is the return on the gold stock Index at time t, GPR_t is the gold price return denominated in US dollar at time t, FXR_t is the foreign exchange return of Australian dollar in terms of US dollar at time t, R_m,t is the market return at time t, and _Et is the random error term at time t.

Findings – The paper finds that the values of gold beta are consistently greater than one, implying the sensitive nature of firms’ stock returns to gold price changes. This also suggests that investors holding gold mining stock would receive higher percentage increases in stock returns from a percentage increase in gold price returns, as opposed to investors holding gold bullion. Furthermore, these values have changed substantially over time with significant changes in gold price volatility. The most important and consistent relationship that we find is the impact of firms’ hedging behavior on their respective gold betas. This is consistent with Tufano’s study. It implies that firms, which hedge a greater proportion of their gold reserves, are less sensitive to movements in gold prices. The finding therefore supports the risk management theory that hedging increases shareholder’s wealth. However, cash operating costs, cash reserves and the level of gold production seem to influence very little on the firms’ exposure to gold price changes.

Originality/value – This study is of interest and important to the stock mining companies and investors because the extent of the effect of gold price movements on the stock returns of gold mining companies has significant impacts on returns for both firms and investors especially in their risk management and investment decisions, respectively.

A comparative assessment of a-lipoic acid N-phenylamides as non-steroidal androgen receptor antagonists both on and off gold nanoparticles

A group of α-lipoic acid N-phenylamides were synthesized employing a variety of amide coupling protocols utilizing electron deficient anilines. These compounds were then assessed for their ability to block androgen-stimulated proliferation of a human prostate cancer cell line, LNCaP. These structurally simple compounds displayed anti-proliferative activities at, typically, 5–20 μM concentrations and were comparable to a commonly used anti-androgen Bicalutamide®. The inclusion of a disulfide (RS-SR) moiety, serving as an anchor to several metal nanoparticle systems (Au, Ag, Fe₂O₃, etc.), does not impede any biological activity. Conjugation of these compounds to a gold nanoparticle surface resulted in a high degree of cellular toxicity, attributed to the absence of a biocompatible group such as PEG within the organic scaffold.