Au-Based Thin-Film Metallic Glasses for Propagating Surface Plasmon Resonance-Based Sensor Applications.

We deposited Au-Cu-Si, an Au-based thin-film metallic glass (TFMG) of ∼50 nm thickness, as the activation layer for propagating surface plasmon resonance (PSPR)-based sensors on a BK7 glass substrate to substitute the commonly used gold layer. The film composition was tuned to yield the maximum Au content (∼65 at %), while the structure remained amorphous. The results showed that the Au-based TFMG could support surface plasmon resonance and gave rise to the extinction in the angle-resolved reflection spectrum. Using deionized water and ethyl alcohol with the refractive index difference of ∼0.03 as the analytes, the angle shift given by Au-based TFMG was 4° compared to 5° given by the Au film. Hence, Au-based TFMG is feasible to be used as the activation layer in PSPR-based sensors. Compared to the Au film, Au-based TFMG has the advantages of being less expensive, lacking grain boundary scattering, better adhesion to the substrate, and higher resistance to scratch and corrosion because of its amorphous structure with excellent mechanical properties.

Correlations between 18F-FDG PET/CT parameters and pathological findings in patients with rectal cancer.

PURPOSE: This study examined the correlations between F-FDG PET/CT results and tumor specimen pathology in patients with rectal cancer. METHODS: Sixty-seven patients with rectal cancer who had received preoperative PET/CT were included in this study. Autosegmentation methods were used to determine the maximum PET/CT-based tumor length (TL), tumor width (TW), and metabolic tumor volume for each patient. The TL and TW values were compared with the maximum pathological length and width of the tumor specimen. To forecast the pathological T and N stages, a receiver operating characteristic curve was created for each parameter to evaluate its predictive ability. Logistic regression analysis was used to identify the predictors of pathology. RESULTS: The values of 30% of maximum uptake for TL and 40% of maximum uptake for TW provided the best match with the maximum pathological tumor length and width (Pearson r = 0.72, P < 0.001; r = 0.44, P < 0.001, respectively). Metabolic tumor volume with a fixed threshold of 2.5 emerged as an independent factor for predicting the pathological T3 or T4 stage (P = 0.001; odds ratio, 1.81; 95% confidence interval, 1.26-2.60). CONCLUSIONS: Preoperative PET/CT can be used as a supplemental tool in predicting pathological findings for patients with rectal cancer requiring operation.