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【Objective】Aiming at the problems of low spectral efficiency and limited system throughput in Optical Quadrature Spatial Modulation (OQSM), a Signed Optical Quadrature Spatial Modulation (SOQSM) scheme is proposed in Free Space Optical Communication (FSOC) in this paper. In addition, in view of the fact that the channel used in the performance analysis of OQSM is not suitable for all turbulence, this paper also adopts the Málaga channel, which is suitable for all turbulence intensities to analyze the bit error performance of the system.【Methods】First, the scheme divides the input binary bit stream into five parts at the sending end. The first part is used for constellation symbol mapping, and the last four parts are used for laser mapping. Then, the constellation symbol mapping is used to transmit the real and imaginary parts of the constellation symbol and its inverse symbol. The laser mapping is divided into two parts, the in-phase phase and the quadrature phase, which are used to activate the laser sequence mapping. Finally, after transmitting through the channel, the signal received and processed at the receiving end.【Results】Compared with OQSM, SOQSM carries an additional2log2Nt bits of information in the space domain within a transmission period. The upper bound of the average bit error rate is then calculated in the symbol domain and the space domain respectively. Finally, the upper bound of the average bit error rate of the SOQSM scheme is obtained, and the method of calculating the upper bound of the average bit error rate has good convergence. This solution greatly improves the spectral efficiency and transmission rate of the system, and has good bit error rate performance.【Conclusion】The Monte Carlo simulation results show that compared with Optical Spatial Modulation (OSM) and OQSM, the bit error performance of the SOQSM scheme is better when the spectral efficiency is the same. The bit error rate can reach 10-6 when the signal-to-noise ratio is 16dB. When the modulation order is the same, the bit error performance of SOQSM is better, especially when the signal-to-noise ratio is high. It is also shown that the simulation and theory fit well. In the Málaga channel, the bit error rate performance of the weak turbulence is better. In addition, different turbulence intensities have little influence on the trend of the bit error rate performance of the SOQSM scheme. However, with the increase of the signal-to-noise ratio, the influence will gradually increase. Therefore, SOQSM has better bit error rate performance than OQSM and OSM.

The COVID-19 pandemic has forced us to engage in the ubiquitous use of virtual interpreting teaching and learning. The sudden shift of teaching mode has resulted in unplanned challenges. The main concerns among teachers and students include teaching quality and learning effectiveness. To examine the effectiveness of interpreting teaching and learning online, we conducted a survey about students' perceptions of satisfaction concerning online interpreting teaching and learning via an online platform. This survey is composed of questions to measure student satisfaction from six aspects, namely, instructor, technology, setup, interaction, outcomes, and overall. Results showed that the shift to abrupt online interpreting teaching and learning did not have any significant impact on teaching quality and learning effectiveness. Findings also highlighted the need for further investigation of self-regulation and self-directiveness in online interpreting teaching and learning. Essential pedagogical tasks can be conducted online (e.g., triangulation exercises, relays, handover, and channel switching). Implications are provided based on the findings.

Recent years have witnessed a growing interest in case studies and surveys by researchers of second language acquisition (SLA) and cognitive (neuro-)science to probe into the group of exceptionally talented multilingual learners or polyglots who can understand and speak an impressive number of multiple foreign languages other than their own mother tongue. The current paper reviews these latest developments and elucidates the phenomenon of (hyper-)polyglottism by tracing and analyzing its definitions and synthesizing and highlighting the key findings of case studies and large-scale surveys. Specifically, we aim to illuminate the complex and intricate relationships between hyperpolyglots' exceptional multilingual talents and their individual differences in language aptitude and other cognitive abilities such as IQ, personality traits, motivational characteristics, and language genetic variations, as well as their brain mechanisms and neural networks. The present paper calls upon concerted efforts from multiple disciplines to determine the critical cognitive abilities and pivotal developmental stages underlying the exceptional performance of these multilingual talents and hyperpolyglots.

Electrochemical conversion of CO2 into formate is a promising strategy for mitigating the energy and environmental crisis, but simultaneously achieving high selectivity and activity of electrocatalysts remains challenging. Here, we report low-dimensional SnO2 quantum dots chemically coupled with ultrathin Ti3C2Tx MXene nanosheets (SnO2/MXene) that boost the CO2 conversion. The coupling structure is well visualized and verified by high-resolution electron tomography together with nanoscale scanning transmission X-ray microscopy and ptychography imaging. The catalyst achieves a large partial current density of -57.8 mA cm-2 and high Faradaic efficiency of 94% for formate formation. Additionally, the SnO2/MXene cathode shows excellent Zn-CO2 battery performance, with a maximum power density of 4.28 mW cm-2, an open-circuit voltage of 0.83 V, and superior rechargeability of 60 h. In situ X-ray absorption spectroscopy analysis and first-principles calculations reveal that this remarkable performance is attributed to the unique and stable structure of the SnO2/MXene, which can significantly reduce the reaction energy of CO2 hydrogenation to formate by increasing the surface coverage of adsorbed hydrogen.

Anion exchange membrane fuel cells are limited by the slow kinetics of alkaline hydrogen oxidation reaction (HOR). Here, we establish HOR catalytic activities of single-atom and diatomic sites as a function of *H and *OH binding energies to screen the optimal active sites for the HOR. As a result, the Ru-Ni diatomic one is identified as the best active center. Guided by the theoretical finding, we subsequently synthesize a catalyst with Ru-Ni diatomic sites supported on N-doped porous carbon, which exhibits excellent catalytic activity, CO tolerance, and stability for alkaline HOR and is also superior to single-site counterparts. In situ scanning electrochemical microscopy study validates the HOR activity resulting from the Ru-Ni diatomic sites. Furthermore, in situ x-ray absorption spectroscopy and computational studies unveil a synergistic interaction between Ru and Ni to promote the molecular H2 dissociation and strengthen OH adsorption at the diatomic sites, and thus enhance the kinetics of HOR.

In the new online learning environment where information technology and education are integrated, it is important to understand the learning patterns of online learners and then predict their learning outcomes to improve learning effectiveness of online learners. In this paper, we collect students’ online learning behavior data through an online learning platform and further investigate the influence mechanism between online learning behavior characteristics and learning performance with the help of the OCCP classification model and the 3D S-F-T model. Meanwhile, the Light GBM algorithm is based on its advantages in noise and distributed processing based on its high accuracy and strong generalization ability in classification problems. The Light GBM algorithm constructs the performance prediction model for the selected learning behavior feature data. The results show that the accuracy of academic achievement prediction based on the Light GBM model is 0.85, and the accuracy of sample prediction classification is H (85%), M (73%) and L (89%), indicating that the model is effective for academic achievement prediction. The experimental results confirm that the prediction method can more accurately identify at-risk students and provide more intuitive and accurate feedback on learners’ problems and deficiencies in the learning process to support the implementation of personalized education interventions.

Photonic crystals are extensively explored to replace inorganic pigments and organic dyes as coloring elements in printing, painting, sensing, and anti-counterfeiting due to their brilliant structural colors, chemical stability, and environmental friendliness. However, most existing photonic-crystal-based pigments can only display monochromatic colors once made, and generating multicolors has to start with designing different building blocks. Here, a novel photonic pigment featuring highly tunable structural colors in the entire visible spectrum, made by the magnetic assembly of monodisperse nanorods into body-centered-tetragonal photonic crystals, is reported. Their prominent magnetic and crystal anisotropy makes it efficient to generate multicolors using one photonic pigment by magnetically controlling the crystal orientation. Further, the combination of angle-dependent diffraction and magnetic orientation control enables the design of rotation-asymmetric photonic films that display distinct patterns and encrypted information in response to rotation. The efficient multicolor generation through precise orientational control makes this novel photonic pigment promising in developing high-performance structural-colored materials and optical devices.

We investigated the somatic mutations and key driving factors of cervical cancer by whole exome sequencing . We found 22,183 somatic single nucleotide variations (SNVs) in 52 paired samples. Somatic SNVs in cervical cancer were significantly higher than those in high-grade intraepithelial lesion and low-grade squamous intraepithelial lesion groups (P < 0.05). C → T/G accounted for 44.12% of base substitution. Copy number variation (false discovery rate < 0.05) was found in 57 chromosome regions. The three regions with significant differences between cervical cancer and non-cervical cancer groups were 1q21.1, 3q26.33, and 13q33.1, covering genes related to tumor proliferation, differentiation, and apoptosis. The frequency of human papillomavirus (HPV) insertion/integration and the number of “tCw” mutations in the cervical cancer group were significantly higher than those in the non-cervical cancer group (P < 0.05). The total number of mutations was positively correlated with the number of “tCw” mutations (R 2 = 0.7967). HPV insertion/integration (OR = 2.302, CI = 1.523–3.589, P = 0.0005), APOBEC enrichment (OR = 17.875, CI = 2.117–150.937, P = 0.001), and HLA-B*39 in HLA-I (OR = 6.435, CI = 0.823–48.919, P = 0.0042) were risk factors for cervical cancer, while HLA-DQB1*05 in HLA-II was a protective factor (OR = 0.426, CI = 0.197–0.910, P = 0.032). Conclusively, HPV insertion/integration, APOBEC mutagenesis, and HLA polymorphisms are high-risk factors for cervical cancer and may be causes of genome instability and somatic mutations. This study provides experimental data for revealing the molecular mechanism of cervical cancer.

Translation policy, although an essential topic in the domain of language policy, has been understudied in China. Macau, as the earliest encounter point between the western and oriental cultures in Modern China, has been undeservingly neglected in this aspect, although its translation activities have never been interrupted since the Ming Dynasty. As such, this article sets out to trace the development of the translation policy in Macau (from its establishment to its handover to China in 1999). In particular, we will focus on tracing the historical evolution and development of the translation policy in Macau in the time span of over 400 years since the Portuguese establishment in 1557. The purpose is to cast a critical eye on its experiences in translation policymaking, using examples from official regulations, existing studies, and bibliometric data. We reconceptualize translation policy to entail the aspects of translation management, translation practices, and beliefs. Overall, the translation policy of Macau contributes to remapping the translation policy of China as important footnotes to the fuller picture of several essential historical periods.

The present paper discusses how insights from translanguaging theory and pedagogy can help inform and promote genre pedagogy for teaching business communication courses such as writing and translation. To this end, the first part traces and reviews the developments of genre theory and pedagogy in tandem with translanguaging theory and pedagogy, thus teasing out their similarities and differences in historical roots, core premises, theoretical frameworks, and research methodologies. In light of these integrated accounts, the second part of the paper proposes a genre-based pedagogical framework augmented with key tenets and general principles of translanguaging pedagogy to design and implement task activities and classroom practice in teaching business communication courses in the Greater Bay Area (GBA). The paper then outlines perceivable advantages and potential challenges to the application of this translanguaging-informed genre-based pedagogical approach in curriculum design and professional training practice in superdiverse megapolis regions such as the GBA.

Pursuing active and durable water splitting electrocatalysts is of vital significance for solving the sluggish kinetics of the oxygen evolution reaction (OER) process in energy supply. Herein, theoretical calculations identify that the local distortion-strain effect in amorphous RuTe2 system abnormally sensitizes the Te-pπ coupling capability and enhances the electron-transfer of Ru-sites, in which the excellent inter-orbital p-d transfers determine strong electronic activities for boosting OER performance. Thus, a robust electrocatalyst based on amorphous RuTe2 porous nanorods (PNRs) is successfully fabricated. In the acidic water splitting, a-RuTe2 PNRs exhibit a superior performance, which only require a cell voltage of 1.52 V to reach a current density of 10 mA cm-2. Detailed investigations show that the high density of defects combine with oxygen atoms to form RuOxHy species, which are conducive to the OER. This work offers valuable insights for constructing robust electrocatalysts based on theoretical calculations guided by rational design and amorphous materials.