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A reflective dual-function beam splitter with bilayer trapezoidal structure is presented, which exhibits two standalone functionalities under normal incidence at 1550 nm. The performance of the bilayer trapezoidal structure is thoroughly investigated using simulated annealing algorithm and rigorous coupled-wave analysis, with validation conducted through finite element method. The findings demonstrate that this grating possesses exceptional characteristics, offering a wide incident bandwidth and manufacturing tolerance. The grating demonstrates a consistent three-port output with an efficiency of 32.36% for ±2nd order and 33.02% for 0th order at transverse electric polarization. By the same token, for transverse magnetic polarization, the grating is capable of achieving similar five-port output, exhibiting efficiencies of 19.98%, 19.51%, and 19.37% for the 0th, ±1st , and ±2nd diffraction orders, individually. Therefore, this proposed splitter has a high reference value in the research of optical communication, laser, optical imaging, and other fields. [ABSTRACT FROM AUTHOR]

Background: We sought to determine the diagnostic efficacy of Breast-specific gamma imaging (BSGI) in Chinese women with BI-RADS 4 category lesions and to compare this efficacy to that of ultrasound/mammography.Methods: We retrospectively analyzed data from 177 women that had undergone BSGI of BI-RADS 4 category lesions originally detected via ultrasound and/or mammography.Results: Of these 177 cases, 117 (66.1%) were malignant lesions and 60 (33.9%) were benign. The sensitivity, specificity, positive predictive values, and negative predictive values of BSGI were 94.9% (111/117), 78.3% (47/60), 89.5% (111/124), and 88.7% (47/53), respectively. The specificity and positive predictive values for mammography were 48.3% (29/60) and 77.5% (107/138), while for ultrasound they were 53.3% (32/60) and 79.6% (109/137), respectively. The sensitivity and specificity of BSGI for the detection of lesions ≤1 cm in size were 90.9% (10/11) and 88.0% (22/25), respectively, while for breast lesions >1 cm in size these values were 94.3% (100/106) and 71.4% (25/35), respectively. In addition, BSGI sensitivity and specificity values for dense breast tissue were 94.0% (79/84) and 78.0% (39/50), respectively, whereas for non-dense breast tissue these vales were 97.0% (32/33) and 80.0% (8/10), respectively. The sensitivity of BSGI for invasive ductal carcinomas (IDC) and ductal carcinomas in situ (DCIS) was 98.9% (95/96) and 75.0% (9/12), respectively. The tumor to normal tissue ratio of BSGI for malignant lesions was significantly higher than for benign lesions (2.18 ± 1.17 vs 1.66 ± 0.40, t = 7.56, P<0.05).Conclusions: These results indicate that BSGI is highly sensitive for the detection of such lesions, achieving good positive/negative predictive values. This suggests that for IDC in particular, BSGI is superior to ultrasound and mammography for the diagnosis of BI-RADS 4 category lesions, although this was less apparent for the diagnosis of DCIS lesions. BSGI exhibited excellent performance in dense breast tissue and for the detection of lesions ≤1 cm in size. [ABSTRACT FROM AUTHOR]

An integrated system incorporating a nuclear unit, multi-stage flash desalination, and proton exchange membrane electrolyzer is proposed for peak shaving. The extraction steam is used for seawater desalination to produce freshwater, the generator output power is employed to drive the electrolyzer for hydrogen production, and the electrolyzer outlet water heats the feedwater for power boosting. Thermodynamic analysis shows that 53.76 MW is used for seawater desalination-hydrogen production (electrolyzer voltage =2.0 V). The system efficiency is 37.44 % with output hydrogen energy of 37.86 MW, and the specific energy consumption is 4.72 kWh/Nm3. The electrolyzer exergy efficiency of the integrated system is 81.94 %, higher than the standalone electrolyzer with 61.17 %. Sensitivity analysis shows higher voltage and lower water flow rates are conducive to higher hydrogen production rates. Economic analysis shows that the cost of hydrogen production is 15.16 CNY/kg and the annual net income can reach 7.68·106 CNY. • Nuclear unit coupled with MSF desalination and PEM electrolyzer for polygeneration. • Whole-process seawater desalination-hydrogen production for peak shaving. • Real internal temperature distribution of the electrolyzer is revealed. • The integrated system is subject to thermodynamic and economic analysis. [ABSTRACT FROM AUTHOR]