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In the development of silicon photonics, the continued downsizing of photonic integrated circuits will further increase the integration density, which augments the functionality of photonic chips. Compared with the traditional design method, inverse design presents a novel approach for achieving compact photonic devices. However, achieving compact, reconfigurable photonic devices with the inverse design that employs the traditional modulation method exemplified by the thermo-optic effect poses a significant challenge due to the weak modulation capability. Low-loss phase change materials (PCMs) exemplified by Sb2Se3 are a promising candidate for solving this problem benefiting from their high refractive index contrast. In this work, we first developed a robust inverse design method to realize reconfigurable silicon and phase-change materials hybrid photonic devices including mode converter and optical switch. The mode converter exhibits a broadband operation of >100 nm. The optical switch shows an extinction ratio of >25 dB and a multilevel switching of 41 (>5 bits) by simply changing the crystallinity of Sb2Se3. Here, we experimentally demonstrated a Sb2Se3/Si hybrid integrated optical switch for the first time, wherein routing can be switched by the phase transition of the whole Sb2Se3. Our work provides an effective solution for the design of photonic devices that is insensitive to fabrication errors, thereby paving the way for high integration density in future photonic chips.

When facing increasingly complex and fast-changing strategic situation, powerful strategic management system is crucial for large-scale power grid enterprises to ensure scientific decision-making, coordinated action and efficient management. This paper analyzes the new strategic management situation of large-scale power grid enterprises under the background of the integrated development of digital revolution and energy revolution. Based on the new situaiton, this paper carries out the demand analysis of the optimization of strategic management mechanism for power grid enterprises, and puts forward the core content of the strategic closed-loop management mechanism optimization. The mechanism optimization will ensure the forward-looking of power grid enterprises’ strategy formulation under the background of digital transformation. Additionally, the mechanism optimization will promote accurate identification of changes, scientific response and effective prevention of strategic risks.

This study aimed to assess vaginal progesterone's effect on different populations and performed comparation between women with varied risk factors. Embase, PubMed, Cochrane library (CENTRAL) were searched without restriction to language up to February 25, 2021. Randomized controlled trials (RCTs) assessing vaginal progesterone administered to women at risk of preterm birth at <37 weeks. Two reviewers independently extracted data, and pooled relative risk (RR) with 95% confidence intervals (CIs) was calculated as well. Women with short cervix have a significantly lower risk of preterm birth at <34 weeks (pooled RR = 0.65; 95% CI: 0.55–0.77; I2 = 0; p < 0.001; nine studies) and some neonatal morbidities; interaction tests showed that effect of vaginal progesterone differs significantly between women with short cervix and those with other risk factors (history of preterm birth, exclusive twin gestation, and vaginal bleeding). Evidences of this study showed that singleton gestations, as well as women with short cervix, benefit from vaginal progesterone in preventing preterm birth at <34 weeks and some neonatal morbidities. Women with short cervix are populations who benefit the most among other risk populations. Key Points Vaginal progesterone reduces preterm birth and neonatal morbidities. Vaginal progesterone effects on some specific populations. Women with short cervix benefit the most. [ABSTRACT FROM AUTHOR]

The functional differences between state-owned capital investment companies and production-oriented state-owned enterprises determine the need to reconstruct the performance evaluation system of state-owned capital specialized operation. Based on the goal of specialized operation of state-owned capital, this paper puts forward the ideas and principles of selecting performance indicators, and constructs the evaluation index system.