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Abstract We propose a hetero-nano-fin structure to further improve the efficiency of Pancharatnam–Berry phase metasurfaces. Two hetero-nano-fin types, MgF2/GaN and MgF2/Nb2O5, were investigated. The overall polarization conversion efficiency (PCE) improved from 52.7 to 54% for the MgF2/GaN nano-fin compared with the bare GaN nano-fin. The overall PCE of the Nb2O5 nano-fin was 1.7 times higher than that of the GaN nano-fin. The overall PCE improved from 92.4% up to 96% after the application of MgF2 antireflection. Moreover, the antireflection improves efficiency by an average of 4.3% in wavelengths from 450 to 700 nm. Although the increment of energy seems minimal, antireflection is crucial for a metasurface, not only enhancing efficiency but also reducing background signal of a meta-device.

Electrocatalytic CO2 reduction reaction (CO2RR) conducted in a flow‐based device exhibits a substantial enhancement in Faradaic efficiency and catalytic current density compared to a conventional H‐type configuration. This highlights the distinct catalytic environment and behavior inherent in flow cells as opposed to H cells. To investigate the authentic properties of a catalyst within a flow‐based device, customized flow cells have been specifically devised for operando techniques during CO2RR and CORR, rather than resorting to an in‐situ three‐electrode H‐type configuration with its disparate catalytic environment and performance. This approach ensures a catalytic environment identical to that employed in electrochemical measurements. This review delineates the disparities between H‐type and flow‐based cells as well as the operando techniques tailored for flow‐based devices, including X‐ray absorption spectroscopy and Raman spectroscopy, preserving a consistent catalytic environment. It also compiles recent findings on copper‐based systems using operando flow‐based devices. The operando insights reveal a significant augmentation in catalytic current density, impacting both chemical properties and crystal structures. Furthermore, the observation of various catalytic intermediates enriches our comprehension. In essence, the application of operando techniques to flow‐based devices furnishes a comprehensive understanding of the catalytic behavior exhibited by diverse systems, propelling progress toward achieving Net Zero emissions. [ABSTRACT FROM AUTHOR]

Developing ruthenium‐based heterogeneous catalysts with an efficient and stable interface is essential for enhanced acidic oxygen evolution reaction (OER). Herein, we report a defect‐rich ultrathin boron nitride nanosheet support with relatively independent electron donor and acceptor sites, which serves as an electron reservoir and receiving station for RuO2, realizing the rapid supply and reception of electrons. Through precisely controlling the reaction interface, a low OER overpotential of only 180 mV (at 10 mA cm−2) and long‐term operational stability (350 h) are achieved, suggesting potential practical applications. In situ characterization and theoretical calculations have validated the existence of a localized electronic recycling between RuO2 and ultrathin BN nanosheets (BNNS). The electron‐rich Ru sites accelerate the adsorption of water molecules and the dissociation of intermediates, while the interconnection between the O‐terminal and B‐terminal edge establishes electronic back‐donation, effectively suppressing the over‐oxidation of lattice oxygen. This study provides a new perspective for constructing a stable and highly active catalytic interface. [ABSTRACT FROM AUTHOR]

In this study, the phase modulation ability of a dielectric Pancharatnam–Berry (PB) phase metasurface, consisting of nanofins, is theoretically analyzed. It is generally considered that the optical thickness of the unit cell of a PB-phase metasurface is λ/2, i.e., a half-waveplate for polarization conversion. It is found that the λ/2 is not essential for achieving a full 2π modulation. Nevertheless, a λ/2 thickness is still needed for a high polarization conversion efficiency. Moreover, a gradient phase metasurface is designed. With the help of the particle swarm optimization (PSO) method, the wavefront errors of the gradient phase metasurface are reduced by fine-tuning the rotation angle of the nanofins. The diffraction efficiency of the gradient phase metasurface is thus improved from 73.4% to 87.3%. This design rule can be utilized to optimize the efficiency of phase-type meta-devices, such as meta-deflectors and metalenses.

The controlled attenuation parameter (CAP) measurement obtained from FibroScan® is a low-risk method of assessing fatty liver. This study investigated the association between the FibroScan® CAP values and nine anthropometric indicators, including the abdominal volume index (AVI), body fat percentage (BFP), body mass index (BMI), conicity index (CI), ponderal index (PI), relative fat mass (RFM), waist circumference (WC), waist–hip ratio (WHR), and waist-to-height ratio (WHtR), and risk of non-alcoholic fatty liver disease (fatty liver). We analyzed the medical records of adult patients who had FibroScan® CAP results. CAP values <238 dB/m were coded as 0 (non- fatty liver) and ≥238 dB/m as 1 (fatty liver). An individual is considered to have class 1 obesity when their body mass index (BMI) ranges from 30 kg/m2 to 34.9 kg/m2. Class 2 obesity is defined by a BMI ranging from 35 kg/m2 to 39.9 kg/m2, while class 3 obesity is designated by a BMI of 40 kg/m2 or higher. Out of 1763 subjects, 908 (51.5%) had fatty liver. The BMI, WHtR, and PI were found to be more strongly correlated with the CAP by the cluster dendrogram with correlation coefficients of 0.58, 0.54, and 0.54, respectively (all p < 0.0001). We found that 28.3% of the individuals without obesity had fatty liver, and 28.2% of the individuals with obesity did not have fatty liver. The BMI, CI, and PI were significant predictors of fatty liver. The BMI, PI, and WHtR demonstrated better predictive ability, indicated by AUC values of 0.72, 0.68, and 0.68, respectively, a finding that was echoed in our cluster group analysis that showed interconnected clustering with the CAP. Therefore, of the nine anthropometric indicators we studied, the BMI, CI, PI, and WHtR were found to be more effective in predicting the CAP score, i.e., fatty liver. [ABSTRACT FROM AUTHOR]

Gender equality laws and gender mainstreaming policies are transforming police forces that once were exclusively male. However, images of police masculinity and male-centered bravery persist at both public and institutional levels, frequently marginalizing female officers in the process. Beginning with the assumption that effective police work requires far more than simple physical-force masculinity, this study investigates the structural practices that form and consolidate ideological links between that masculinity and police work. The findings suggests that police work definitions tend to prioritize physical force and attack capacity, thereby constructing a gender category-linked hierarchy of wu-wen strategies. The resulting systemic political and social orders justify the presumption that men are more suited to police work, thereby bolstering the above-mentioned ideological links. To achieve gender inclusivity, the masculinity cult in policing must be reexamined, mechanisms that value force must be dismantled, and job definitions must be expanded to incorporate more diverse policing practices. [ABSTRACT FROM AUTHOR]