RESUMO
Thermochromic smart windows are widely developed to modulate building energy exchange to save building energy consumption. However, most smart windows have fixed working temperatures, moderate energy-saving efficiency, and are not suitable for diverse (cold and hot) climates. Here smart windows with strong temperature modulation over a broad range of hydrogels with adjustable transition temperatures for all-weather building temperature regulation in different climates are reported. Thermochromic poly(N-isopropylacrylamide-co-N, N-dimethylacrylamide) hydrogels, with lower critical transition temperatures ranging from 32.5 to 43.5 °C, are developed for smart windows with solar modulation up to 88.84% and intrinsic transmittance up to 91.30% over full spectrum without energy input. Simulated indoor investigations are performed in different cities from 23 °N to 39 °N from winter to summer. The results indicate that smart windows have a strong solar modulation in summer to reduce indoor temperature up to 7.3 °C and efficient heat conservation in winter to save energy up to 4.30 J m-3 , in comparison to glass windows. Smart windows with grid patterns and Chinese kirigami are fabricated by using 3D printing of the hydrogels to achieve both solar modulation and light incidence. The strategy offers an innovative path for thermochromic smart windows for low carbon economy.
RESUMO
BACKGROUND/AIMS: To date, several positron emission tomography/computed tomography (PET/CT) radiotracers including fluorine-18 fluorodeoxyglucose (18F-FDG), carbon-11 labeled choline (11C-choline), 18-F fluorocholine (18F-FCH) and carbon-11 acetate (11C-acetate) have already been assessed in the application of prostate cancer (PCa) diagnosis to some extent, the diagnostic efficiency of these radiotracers still remain controversial. As a result of this, we carried out this meta-analysis for the purpose of comparing the diagnostic accuracy among four PET/CT radiotracers. METHODS: A systematical literature search for articles was performed until July 3, 2015. We implemented all analysis using the statistical software of STATA12 and quality assessment was performed using QUADAS-2. RESULTS: A total of 56 studies containing 3,586 patients were included in this meta-analysis. Parameter estimates of the overall analysis are as follows: sensitivity, 0.80 (95% CI: 0.74-0.85); specificity, 0.84 (95% CI: 0.77-0.89) and area under roc curve-AUC of SROC, 0.89 (95% CI: 0.86-0.91), indicating a relatively high level of accuracy in diagnosis of PCa. When different radiotracers of PET/CT were compared, 18F-FCH-PET/CT was ranked as the most favorable with the highest value of AUC (AUC = 0.94; 95% CI: 0.92-0.96) whereas 18F-FDG was the least favorable (AUC = 0.73, 95% CI: 0.69-0.77). CONCLUSION: This study suggested that PET/CT imaging plays an invaluable role in the diagnosis of PCa and 18F-FCH-PET/CT was considered as a superior diagnostic tool over other radiotracers. More attention should be paid to the diagnostic efficiency of the four radiotracers particularly for PCa patients with different clinical stages.
