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This study investigates the impact of geopolitical risk (GPR) on consumption-based carbon (CCO2) emissions as well as the moderating role of environmental policy stringency (EPS) on the above relationship. Based on data collected from 27 countries from 1990 to 2020, the basic results from the sample of the study indicate that GPR accelerates CCO2 emissions. Quantile regression results reveal that the effect of GPR is more pronounced in countries with higher CCO2 emissions. Moreover, EPS weakens the escalating effect of GPR on CCO2 emissions. The robust test results validate the findings reported in the basic regression model. The heterogeneity test indicates that the impact of GPR on CCO2 emissions is greater in developing countries compared in developed countries. The study also proposes these policy implications based on the findings: (1) countries should ensure a stable political environment, establish a robust legal system and promote energy transition; and (2) the scope of environmental taxes should be expanded where different tax rates should be imposed in order to be useful in reducing CCO2 emissions. [ABSTRACT FROM AUTHOR]

Background: Postoperative anastomotic leakage (PAL) is a serious complication of gastric cancer surgery. Although perioperative management has made considerable progress, anastomotic leakage (AL) cannot always be avoided. The purpose of this study is to evaluate whether intraoperative leak testing (IOLT) can reduce the incidence of PAL and other postoperative outcomes in gastric cancer surgery. Materials and methods: In this meta-analysis, we searched the PubMed, Embase, and Cochrane Library databases for clinical trials to assess the application of IOLT in gastric cancer surgery. All patients underwent laparoscopic radical gastrectomy for gastric cancer surgery. Studies comparing the postoperative outcomes of IOLT and no intraoperative leak testing (NIOLT) were included. Quality assessment, heterogeneity, risk of bias, and the level of evidence of the included studies were evaluated. PAL, anastomotic-related complications, 30-day mortality, and reoperation rates were compared between the IOLT and NIOLT group. Results: Our literature search returned 721 results, from which six trials (a total of 1,666 patients) were included in our meta-analysis. Statistical heterogeneity was low. The primary outcome was PAL. IOLT reduced the incidence of PAL [2.09% vs 6.68%; (RR = 0.31, 95% Cl 0.19–0.53, P < 0.0001]. Anastomotic-related complications, which included bleeding, leakage, and stricture, were significantly higher in the NIOLT group than in the IOLT group [3.24% VS 10.85%; RR = 0.30, 95% Cl 0.18–0.53, P < 0.0001]. Moreover, IOLT was associated with lower reoperation rates [0.94% vs 6.83%; RR = 0.18, 95% CI 0.07–0.43, P = 0.0002]. Conclusion: Considering the observed lower incidence of postoperative anastomotic leakage (PAL), anastomotic-related complications, and reoperation rates, IOLT appears to be a promising option for gastric cancer surgery. It warrants further study before potential inclusion in future clinical guidelines. [ABSTRACT FROM AUTHOR]

This study investigates the impact of macroprudential policies on ecological footprint (EF) in the top 11 largest countries. This study uses country-level panel data from these countries, covering the period from 1992 to 2020. Findings indicate that macroprudential policies alleviates ecological footprint in the sample. Macroprudential policies primarily reduce the ecological footprint before medium quantile (50%) while the environmental benefits of the policies end in the later quantiles. Moreover, environmental policy stringency (EPS) amplifies the positive influence of macroprudential policies on environmental sustainability. Estimate results stay the same with basic regression results in the post-global financial crisis (GFC) period while the impact is positive in the pre-GFC period. Finally, other robust tests validate the findings reported in basic regression model. This study suggests that governments should customize various types of macroprudential policies while also considering environmental concerns. The achievement of a sustainable environment can be facilitated by the combined effects of macroprudential policies and EPS. [ABSTRACT FROM AUTHOR]

This study investigates the impact of macroprudential policies on CO2 emissions in G7 and BRIC countries using country-level panel data from 11 countries, covering the period from 1992 to 2020. The findings indicate that macroprudential policies alleviate CO2 emissions in the sample. Quantile regression results reveal that policies can exacerbate CO2 emissions in countries with high levels of CO2 emissions due to carbon leakage. The positive impact of macroprudential policies on sustainable development can be strengthened by high level of globalisation. Moreover, the influence of macroprudential policies stayed the same based on the basic regression results during the post-global financial crisis (GFC) period, while the impact was positive in the pre-GFC period. Finally, robust tests validated the findings reported in the basic regression model. From this, policymakers should prioritise sustainable economic growth when implementing macroprudential policies and leverage the influence of globalisation to amplify their impact on CO2 emissions. Furthermore, it is crucial to strengthen environmental regulations to prevent carbon leakage that result from industries seeking lenient standards. [ABSTRACT FROM AUTHOR]

As an infrastructure of biochemical laboratories, EP tube label plays a significant role in information extraction to meet the limitations of computing power in offline devices and solve the problem that the EP tube label cannot be accurately identified before identification because the label belongs to multi-angle random placement. This paper proposes a light-weight neural network YOLOv4-tiny-ECA to position tubes and a tilt correction method based on Hough transform. First, the EP tube rack is roughly positioned based on the diffuse filling algorithm combined with digital morphological corrosion, and then the EP tubes in the rack are precisely positioned using the light-weight YOLO target detection algorithm combined with the attention mechanism. Next, the baseline is added to the label as the basis for determining the tilt angle. For the valid target, the baseline is extracted using the Hough transform and the tilt angle is calculated by vector fork multiplication. Finally, baseline is removed using image processing algorithm for better recognition results. Our results show that the light-weight YOLO algorithm reduces the network parameters by 56% and computation by 55% while keeping the accuracy rate largely unchanged, the offline positioning tilt correction method can achieve 98.8% accuracy and 0.076 s processing speed for a single test tube on average, which meets the real-time requirement. [ABSTRACT FROM AUTHOR]

Objective: To identify the additional diagnostic value of CNV‐seq over conventional karyotyping on the part of chromosomal abnormalities in prenatal diagnosis. Method: This was a systematic review conducted in accordance with PRISMA criteria. In order to clarify related research, PubMed, Web of Science databases (including Core Collection, BIOSIS Previews, MEDLINE, and so on), The Cochrane Library and Wiley Online Library were searched with the terms: "prenatal diagnosis," "CNV‐seq," "karyotyping," published from January 2010 to May 2022. No language restrictions. RenMan 5.4 was used for the meta‐analysis. Results: Eight studies were included in this systemic review and meta‐analysis, including 11 091 pregnant women with high‐risk pregnancy factors or with structurally abnormal fetus under ultrasound. CNV‐seq detected a 2% (95% CI, −0% to 4%) additional chromosomal anomalies over conventional karyotyping in the six series. A 4% (95% CI, 3%–6%) pooled mean incremental yield of pathogenic CNVs by CNV‐seq over karyotyping was observed, with a 1%–16% range. Conclusion: CNV‐seq, applied in prenatal diagnosis, may detect more chromosomal abnormalities when compared with karyotyping. With the advantages of wide coverage, high throughput, high resolution, no culture, good compatibility, and adjustable sequencing depth, CNV‐seq has high application value in prenatal diagnosis. [ABSTRACT FROM AUTHOR]

Background: Anastomosis-related complications such as bleeding, leakage, and strictures, continue to be serious complications of gastric cancer surgery. Presently, these complications have yet to be reliably prevented. Here we design a comprehensive leak testing procedure which combines gastroscopy, air, and methylene blue (GAM) leak testing. We aimed to evaluated the efficacy and safety of the GAM procedure in patients with gastric cancer. Methods: Patients aged 18–85 years without an unresectable factor as confirmed via CT were enrolled in a prospective randomized clinical trial at a tertiary referral teaching hospital and were randomly assigned to two groups: intraoperative leak testing group (IOLT) and no intraoperative leak testing group (NIOLT). The primary endpoint was the incidence of postoperative anastomosis-related complications in the two groups. Results: 148 patients were initially randomly assigned to the IOLT group (n = 74) and to the NIOLT group (n = 74) between September 2018 and September 2022. After exclusions, 70 remained in the IOLT group and 68 in the NIOLT group. In the IOLT group, 5 patients (7.1%) were found to have anastomotic defects intraoperatively, which included anastomotic discontinuity, bleeding, and strictures. The NIOLT group had a higher incidence of postoperative anastomotic leakage compared to the IOLT group: 4 patients (5.8%) vs 0 patients (0%), respectively. No GAM-related complications were observed. Conclusion: The GAM procedure is an intraoperative leak test that can be performed safely and efficiently after a laparoscopic total gastrectomy. GAM anastomotic leak testing may effectively prevent technical defect-related anastomotic complications in patients with gastric cancer who undergo a gastrectomy. Trial registration: Clinical Trials.gov Identifier: NCT04292496. [ABSTRACT FROM AUTHOR]

Passive daytime radiation cooling (PDRC) has gained considerable attention as an emerging and promising cooling technology. Polymer‐based porous materials are one of the important candidates for PDRC application due to their easy processing, free of inorganic particle doping, and multifunctionality. However, the mechanical properties of these porous materials, which are critical in outdoor services, have been overlooked in previous studies. Herein, a nonsolvent‐induced phase separation (NIPS) method combined with ambient pressure drying to prepare polyethylene‐polysilicate all‐polymer porous coatings is developed. The coatings possess a Cyphochilus beetle‐like skeleton structure with optimal skeleton size, laminated anisotropy, and high volume fraction (64 ± 1%). These structure features ensure a maximum skeleton density without optical crowding, thus enhancing light scattering and stress dispersion, and balancing optical and mechanical properties. The coatings exhibit significant mechanical robustness (only ≈70 µm thickness reduction after 1000 Taber abrasion cycles at a 750 g load without influencing optical performance), durability, optical properties (a solar reflectance of ≈95% and an average near‐normal thermal emittance of ≈96%), and PDRC performance (realizing sub‐ambient cooling of ≈3–6 °C at midday with different weather conditions). The work provides a new solution to improve the practicability of polymer‐based porous coatings in PDRC outdoor services and other fields. [ABSTRACT FROM AUTHOR]

The rupture process of earthquakes at intermediate-depth (∼70–300 km) have rarely been illuminated by a joint analysis of geodetic and seismic observations, hindering our understanding of their dynamic rupture mechanisms. Here we present detailed rupture process of the 2019 M w8.0 Peru earthquake at the depth of 122 km depth, derived with a holistic approach reconciling InSAR and broad-band seismic waveform data. The joint inversion of InSAR observations and teleseismic body waves results in a finite rupture model that extends ∼200 km along strike, with unilateral rupture towards north that lasted for ∼60 s. There are four major slip patches in the finite fault model which are well corresponding to the position and timing of the sources in back-projection and multiple points source results. The largest slip patch, which occurred ∼40 s after the rupture initiation, had a longer and smoother rise time, and radiated much weaker high-frequency seismic waves compared to other smaller slip patches. This distinct frequency-dependent rupture could be explained by a strong dynamic weakening mechanism. We question whether thermal pressurization of pore free water rather than thermal run away could be such a mechanism. Our frequency content analysis could be generalized to study other earthquakes including those deeper than 300 km. [ABSTRACT FROM AUTHOR]

Earthquake source parameters are important for understanding earthquake physics and crustal fault properties. However, strong trade‐offs between parameters (e.g., depth and origin time) and a lack of accurate velocity models and near‐field seismic stations could cause large uncertainties of these parameters in seismic catalogs, particularly for shallow events. To further improve the resolution of earthquake source parameters, we use Interferometric Synthetic Aperture Radar (InSAR) images to derive source solutions of 33 moderate‐size (Mw 4.1–6.6) earthquakes that occurred at shallow depths (<20 km) from November 2014 to July 2020 in western China. After evaluating the uncertainties of the InSAR solutions, we systematically compare the location, centroid depth, focal mechanism and magnitude from InSAR models with that from seismic catalogs. We find that all seismic catalogs generally report deeper (4–10 km) hypocenters or centroid depths. The uncertainties of moment tensor solutions are partially related to the percentage of the non‐double‐couple components in the seismic catalogs. The InSAR solutions indicate that considerable seismic moments (i.e., ∼2×1018 ${2\times 10}^{18}$ Nm) were released in the uppermost crust (i.e., <5 km) in a period of ∼6 years, which is not resolvable in the seismic catalogs. The smooth seismic moment distribution along depth indicates a gradual change of the frictional properties from the surface to the middle crust. As most of the studied earthquakes are located on secondary and/or unmapped faults, these findings imply a considerable portion of velocity‐weakening friction in the uppermost crust along immature, secondary fault systems, which should be included in the seismic hazard evaluation. Plain Language Summary: Uncertainties of parameters that describe earthquake location, fault geometry, and fault slip are generally poorly known in the seismological catalogs. Due to these unknown uncertainties, the distribution of earthquakes in the shallow crust (e.g., <10 km) is not well understood, hindering our understanding of its seismic capacity. Here, we study the moderate‐size earthquakes that occurred in western China from November 2014 to July 2020. We use Interferometric Synthetic Aperture Radar (InSAR) data to obtain surface deformations caused by earthquakes in the shallow crust. We find 33 events (Mw 4.1–6.6) out of 310 earthquakes that have clear InSAR signals, which are used to constrain the source parameters of these earthquakes. We estimate the uncertainties of these InSAR solutions and systematically compare them with the solutions in the seismic catalogs. Our analysis shows that all seismic catalogs report deeper source depth and the horizontal mislocations of the Global Centroid Moment Tensor catalog show geographic correlation features. InSAR solutions also show fault geometry and rupture complexity more precisely than the seismic catalogs. Our results indicate considerable earthquake energy released in the uppermost crust that is not resolvable in the seismic catalogs, which raises additional concerns on the seismic hazard possessed by the shallow earthquakes. Key Points: Coseismic deformations and source solutions of 33 shallow moderate‐size earthquakes (Mw 4.1–6.6) derived from Interferometric Synthetic Aperture Radar (InSAR) dataSource parameters from InSAR solutions and seismic catalogs are systematically compared to estimate their uncertaintiesInSAR solutions show considerable moments released in the uppermost crust, revealing the seismogenic capacity of the shallow crust [ABSTRACT FROM AUTHOR]

Gender differences are essential factors influencing collaborative learning at both individual and group levels. However, few studies have systematically investigated their impact on student performance in the innovative context of STEAM education, particularly in the elementary school setting. To address this research need, this study examined the learning behaviors of 91 sixth graders in a STEAM program, who were classified into three gender groupings, namely, boy-only, girl-only, and mixed-gender groups, and further compared their performance in terms of cognition, interaction, and emotion by both gender and gender group type. The results show that, compared to individual gender differences, the gender group type had a greater impact on students' behavioral performance during STEAM education. While all gender groupings had specific advantages, mixed-gender groups proved to be the most preferable, with benefits such as enhanced higher-order thinking, interaction, and emotional expression. Moreover, the study revealed that both boys and girls acted differently when working with the opposite gender in mixed-gender groups. These research findings have several implications for facilitating STEAM learning in co-ed elementary schools. [ABSTRACT FROM AUTHOR]

The 1,000 km‐long Haiyuan fault is the largest strike‐slip fault system in the northeastern Tibetan Plateau, accommodating part of the plateau's eastward extrusion. However, few large earthquakes have been instrumentally recorded, hindering our understanding of strain partitioning across the fault system. Here, we use synthetic aperture radar images to investigate fault geometries and slip distributions of the adjacent 2016 Mw5.9 and 2022 Mw6.7 Menyuan earthquakes that occurred 35 km apart along the western Haiyuan fault system. The purely strike and purely thrust slips of the 2022 and 2016 events indicate that strain was released separately on shallow steep fault and low‐angle fault at depth. We propose that such strain partitioning is controlled by the ratio between interseismic shear and normal velocities and the branching fault structure beneath the Lenglongling segment. Seismic hazard due to both focal mechanisms has to be considered along the western Haiyuan fault in northeastern Tibet. Plain Language Summary: Apart by 35 km, two earthquakes occurred on 20 January 2016 and 7 January 2022 with the moment magnitude of Mw5.9 and Mw6.7 along the western Haiyuan fault system, near Menyuan county, China. They are the largest events on the Lenglongling (LLL) mountain in past decades and also the only ones with clear surface deformation captured by radar imaging geodesy. Here, we use Synthetic aperture radar images to measure the surface deformations caused by these two events and derive their fault geometries and slip distributions. For the 2022 event, our modeling shows that the rupture propagated on both the LLL and the Tuolaishan (TLS) fault, supporting that the Haiyuan fault system may extend westward through LLL to the TLS fault. The purely thrust‐slip and purely strike‐slip mechanisms of the 2016 and 2022 events indicate the strain partitioning that the shear and normal strain can be released by the strike‐slip event and thrust event separately. Such strain partitioning reminds us to consider seismic hazards due to both shallow strike‐slip and deep thrust earthquakes along the western Haiyuan fault system. Key Points: Slip distributions of the 2016 Mw5.9 and 2022 Mw6.7 Menyuan earthquakes are derived from Sentinel‐1 interferograms and pixel offsetsThe 2022 Menyuan earthquake suggests the Tuolaishan fault may as the continuation of the Haiyuan fault west of the Lenglongling faultCoseismic slip partitioning along the western Haiyuan fault agrees with the interseismic shear‐to‐normal strain ratio and fault geometries [ABSTRACT FROM AUTHOR]

Discussion has been widely used in courses, both online and otherwise, as it provides opportunities for students to construct knowledge through interaction with peers and instructors. Grouping students is a prominent strategy in the use of discussion. However, simply dividing students cannot guarantee active participation and high learning performance. There is therefore a need to pay attention to the structure and/or features of grouping, especially group size and group composition. The study described in this article focuses on the combined effects of group size and group composition in online discussion. It investigates whether students in small groups have different participation behaviors and learning performance compared to students in whole-class discussion. In addition, the influence of group composition is examined by comparing students' participation and learning performance from high, medium, and low social-connected groups. Furthermore, this study also investigates how students' perceived learning experience differs among these three differently-connected group compositions. The results indicate significantly different participation behaviors and learning performance between small-group and whole-class discussion. The effects of group composition are also shown in students' learning behaviors, performance, and perceived experience. The results also reveal both advantages and disadvantages of different group types. The findings are expected to inform the design and implementation of grouping methods and extend our understanding of online discussion. [ABSTRACT FROM AUTHOR]

The growing prevalence of collaborative learning spaces in higher education highlights the importance of student leadership for group learning. Thus, leadership assignment as a common practice in online collaborative learning merits special attention. To investigate the impact of assigned leadership and its key characteristics in promoting team learning in the online context, a semester-long quasi-experiment was conducted with 94 students in a graduate-level blended course. The results revealed significant differences between assigned leaders and group members in certain participating behaviors. However, the impact of assigned leadership on learning outcomes and perceptions was insubstantial. Additionally, student leaders' academic achievement was found to have little impact on group members' learning behaviors and learning outcomes, and mixed results were reported regarding the influence of leader behaviors on group performance. The research findings can inform the crucial decision of leader selection and extend our understanding of leadership in online collaborative learning. [ABSTRACT FROM AUTHOR]

The possibility of using transition metal (TM)/MXene as a catalyst for the nitrogen reduction reaction (NRR) was studied by density functional theory, in which TM is an Fe atom, and MXene is pure Ti3C2O2 or Ti3C2O2−x doped with N/F/P/S/Cl. The adsorption energy and Gibbs free energy were calculated to describe the limiting potentials of N2 activation and reduction, respectively. N2 activation was spontaneous, and the reduction potential-limiting step may be the hydrogenation of N2 to *NNH and the desorption of *NH3 to NH3. The charge transfer of the adsorbed Fe atoms to N2 molecules weakened the interaction of N≡N, which indicates that Fe/MXene is a potential catalytic material for the NRR. In particular, doping with nonmetals F and S reduced the limiting potential of the two potential-limiting steps in the reduction reaction, compared with the undoped pure structure. Thus, Fe/MXenes doped with these nonmetals are the best candidates among these structures. [ABSTRACT FROM AUTHOR]

China accounts for more than 22% of the total energy consumption worldwide. Building energy consumption, among which consumption in public buildings was about 40% took the second place. With the problems of high energy waste, error rate and complexity of the control systems available, an indoor intelligent lighting system based on occupants' location is proposed in this paper to improve the energy efficiency of the current lighting systems indoors. The transmission model of electromagnetic wave in free space is optimized in both aspects of reference signal strength and attenuation coefficient radiation in complex environment dynamically based on which occupants' positions are obtained. The smart lighting system will turn on or off corresponding lights adaptively to provide a more energy efficient platform. Experimental results show that the proposed system is able to improve the energy efficiency of indoor lighting by at least 15%, with a lower error rate below 2% compared with the existing lighting systems based on voice control. [ABSTRACT FROM AUTHOR]

This study is a systematic review of 20 years of research on the usage of virtual reality (VR) in K‐12 and higher education settings, which aims to consolidate, evaluate, and communicate evidence that can inform both the theory and practice of VR‐based instruction. A total of 149 articles were selected from three major academic databases using search strings and manual screening protocols. The literature analysis emphasized four interrelated aspects of VR‐based instruction: instructional context, instructional design, technological affordances, and research findings. The results revealed evolving trends in the VR literature in terms of publication patterns, pedagogical assumptions, equipment usage, and research methodologies, as well as the contextual factors behind VR adoption in education. Additionally, a meta‐analysis was conducted to examine the efficacy of VR‐based instruction, with results indicating an overall medium effect and several moderating factors. Finally, practical implications and a future research agenda for VR‐based instruction are discussed. Lay Description: What is currently known about the subject matter: VR is a promising educational technology with several learning benefits.Research findings on VR‐based education have been conditional and inconclusive.Contemporary research on VR in K‐12 and higher education settings lacks a comprehensive review and meta‐analysis. What this paper adds: This paper systematically reviewed 20 years of empirical research on VR application in K‐12 and higher education.This paper revealed evolving trends in the VR literature in terms of publication patterns, pedagogical assumptions, and equipment usage.This paper synthesised the key pedagogical and technological features of VR interventions.This paper reported an overall medium effect size of VR‐based instruction and several moderating factors. Implications of this study for practitioners: Decision to adopt VR technology should be based on the careful assessment of learning domains and tasks.Embedded functions for learning assessment, collaboration, and data collection are recommended for future VR interventions.Research in VR is needed with focus on advanced technology, cross‐disciplinary comparison, holistic instructional process, and cost‐benefit analysis. [ABSTRACT FROM AUTHOR]

The proliferation of massive open online courses (MOOCs) highlights the necessity of developing accurate and diagnostic evaluation methods to assess the courses' quality and effectiveness. Hence, this study proposes a diagnostic MOOC evaluation (DME) method that combines the Analytic Hierarchy Process algorithm and learner review mining to integrate expert opinions, standardized rubrics, and learner feedback into the evaluation process. For this purpose, 30 MOOCs from the Coursera website were purposively selected and evaluated using the DME method and the results compared with expert evaluation and learner rating scores. The preliminary findings, in general, support the feasibility, accuracy, and diagnostic utility of the DME method and its suitability as a low-cost, sophisticated, and accurate method for MOOC evaluation. Finally, the study discusses several limitations and technical issues of the DME method that should be addressed in future research and practice. [ABSTRACT FROM AUTHOR]

Dielectric properties and electromagnetic (EM) wave absorbing performance of monolithic (SiC/HfC/C)/SiO 2 nanocomposites (denoted as SHCOs) have been investigated in the X-band (8.2–12.4 GHz). The multiphase SHCOs are composed of insulating SiO 2 and SiC/HfC/C nanocomposite fillers (SHC), which fillers composed of semiconducting β-SiC, conductive HfC-Carbon core-shell nanoparticles, and interconnected carbon nanoribbons. Dielectric response indicates that the increased SHC content results in an enhanced imaginary part of the permittivity and dielectric loss, leading to an improved EM absorbing performance. The unique microstructure with an EM wave-transparent SiO 2 matrix is favorable for impedance matching and effective EM wave propagation. The enhanced interface polarization and conduction loss are considered as the key mechanisms for EM wave attenuation. The minimum reflection loss of the SHCOs achieves – 60.7 dB containing 20 vol% of SHC (at 9.98 GHz) with the sample thickness of 3.33 mm, and the effective absorbing bandwidth (EAB) covers ca. 72 % of the X-band. The monolithic (SiC/HfC/C)/SiO 2 nanocomposites with outstanding EM wave absorbing performance are promising candidates for EM application at high temperatures. [ABSTRACT FROM AUTHOR]

Asynchronous online discussion (AOD) is an essential component of blended learning, and role assignment and timing are two important discussion design considerations. With the purpose of improving blended learning through effective AOD design, this study conducted a two-level factorial experiment to explore the main effects and interaction effects of role assignment and timing on blended learning outcome and experiences. In addition, this experiment examined the influence of role assignment and timing on participants' social communication in AOD and the effects of timing on individual role performance in role-based discussion. A total of 114 participants in a blended course were randomly assigned to four experimental conditions: role-based pre-class discussion (n = 29), role-free pre-class discussion (n = 29), role-based post-class discussion (n = 28), and role-free post-class discussion (n = 28). The results showed that the role assignment strategy featured by initiator, supporter, and arguer has led to improved learning experiences in terms of affection, sense of community, and forum experiences, as well as enhanced social communication in AOD; while timing affected the enactment, contribution, and participation of assigned roles in role-based discussions. However, there was no significant interaction between the two AOD strategies. In general, role-based post-class AOD is recommended after face-to-face lesson because of the better learning experience and role performance. • Role assignment and timing had limited impact on blended learning outcomes. • Role assignment enhanced learning experiences and social communication in AOD. • Timing influenced students' capacity of acting and participation degree in role-based discussions. • No interaction effects existed between role assignment and timing strategies. [ABSTRACT FROM AUTHOR]

The development of wide-band microwave absorbing materials based on carbonaceous fillers remains a great challenge. In this study, carbon nanotubes (CNT) assembled coronal hollow clusters with efficient microwave absorbing performance have been obtained through successive hydrothermal and calcination process. Microstructural analysis reveals the distinct features of multiple assembly structures in the fabricated materials. The electromagnetic responses of Ni/CNT assembled clusters were examined across a frequency range of 2–18 GHz. Results demonstrate that the microwave frequency dispersion of electromagnetic parameters and reflection loss of Ni/CNT clusters are strongly influenced by weight loading. Multi-absorbing peaks with reflection loss better than − 40 dB could be achieved, while the equivalent absorbing band for RL < −10 dB covers 3.2–18 GHz, which account for 92.5% of the whole evaluated frequency range, and 62.5% for condition of RL < −20 dB. Furthermore, intrinsic attenuation beyond thickness derived semi-wavelength resonant absorption makes a major contribution to this superior performance. The underlying mechanism of dielectric response was investigated through Cole-Cole analysis and finite element simulation. 'Micro-dipoles' relaxation and hopping relaxation originated from defects within CNT and barrier between CNT, while the high magnetic dissipation capability of Ni nanoparticles make a major contribution to overall absorbing performance. All these are beneficial to regulation and optimization of microwave absorption performance of novel Ni/ CNT functionalized multistage architecture. [Display omitted] • Ni/CNT clusters were prepared through a sample solvothermal method; • Carbon nanotubes were assembled in situ into coronal hollow spherical multilayer carbon nanotube clusters; • The absorption efficiency of CNT is improved by anisotropic strong dielectric loss and multi-layer structure. • The microwave absorption of the new Ni/ CNT functionalized multistage structure greatly improves the performance. [ABSTRACT FROM AUTHOR]

Telomere single-stranded DNA-binding proteins bind to the terminal single-stranded DNA of telomeres, maintaining and protecting the chromosomal end in eukaryotes. This paper focuses on the protective mechanism of single-stranded DNA-binding proteins in plant telomeres. This review summarizes the roles of plant single-stranded DNA-binding proteins and their influence on telomere length and telomerase. This review provides insights into the mechanism and development of single-stranded DNA-binding proteins in plants. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the influence of cutting parameters on the cutting performance of 7075-T651 aluminum alloy under different processing methods. Using finite element software, normal cutting, x-direction ultrasonic vibration cutting, y-direction ultrasonic vibration cutting, and elliptical ultrasonic vibration cutting processes were simulated with various values of the cutting parameters. The results showed that when the cutting speed was between 160 and 280 m/min, with the increase of the cutting speed, the main cutting force value under the four processing methods increases gradually. At 280–320 m/min, the main cutting force value of normal cutting showed a downward trend. The cutting force increased with the increase of feed and cutting depth. At the same time, the increase of cutting speed and feed increased the cutting temperature and the temperature of the blade-to-chip contact area. However, cutting depth had little influence on the temperature during the cutting process. When the cutting parameters changed, the cutting temperatures of the four machining modes were in the following order: elliptical vibration cutting > y-direction vibration cutting > x-direction vibration cutting > normal cutting. When the cutting speed and feed increased, the magnitude and depth of residual stress increased to a certain extent. As the cutting depth increased, the heat generated by the cutting increased, but most of the heat was carried away by the chips, resulting in lower influence of the thermal stress and phase changes on the residual stress. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effects of the cutting and vibration parameters on the machining performance of 7075-T651 aluminum alloy in an unidirectional ultrasonic vibration cutting. Simulation experiments were performed using the AdvantEdge finite element analysis software. The results showed that as the cutting speed and feed rate increased, the cutting force and cutting temperature of the ultrasonic vibrations in the x- and y-directions increased. As the amplitude and frequency increased, they decreased accordingly. The highest temperatures of the rake and relief of the tool were located 0.01–0.02 mm from the cutting edge. With the change in the cutting and vibration parameters, the residual stress curve had a "spoon-shaped" distribution. When the cutting parameters were increased, the magnitude of the residual stress and the depth of the layer increased to a certain extent. With the increase in the vibration parameters, the change in the residual stress value of the ultrasonic vibration in the x direction was small, whereas the residual stress value of the ultrasonic vibration in the y direction increased accordingly. y-direction ultrasonic vibration and conventional cutting experiments were performed on the workpiece. The simulation values of the y-direction ultrasonic vibration cutting agreed well with the experimental values. At the same time, compared with conventional cutting, the ultrasonic vibration cutting exhibited a greatly reduced cutting force and cutting temperature. [ABSTRACT FROM AUTHOR]

• TNF-α producing cells are the dominant population of HBV-specific CD4 T cells in chronic HBV infection. • Increased frequency/dominance of HBV-specific IFN-γ producing CD4 T cells parallels elevated HBV viral clearance. • HBV core-specific TNF-α producing CD4 T cells are associated with liver damage in patients with a hepatitis B flare. • HBV-specific IFN-γ producing CD4 T cells are associated with HBV viral clearance in patients with a hepatitis B flare. • Some HBV-specific IFN-γ producing CD4 T cells might originate from HBV-specific TNF-α producing CD4 T cells during flare. The role of hepatitis B virus (HBV)-specific CD4 T cells in patients with chronic HBV infection is not clear. Thus, we aimed to elucidate this in patients with chronic infection, and those with hepatitis B flares. Through intracellular IFN-γ and TNF-α staining, HBV-specific CD4 T cells were analyzed in 68 patients with chronic HBV infection and alanine aminotransferase (ALT) <2x the upper limit of normal (ULN), and 28 patients with a hepatitis B flare. HBV-specific HLA-DRB1*0803/HLA-DRB1*1202-restricted CD4 T cell epitopes were identified. TNF-α producing cells were the dominant population in patients' HBV-specific CD4 T cells. In patients with ALT <2xULN, both the frequency and the dominance of HBV-specific IFN-γ producing CD4 T cells increased sequentially in patients with elevated levels of viral clearance: HBV e antigen (HBeAg) positive, HBeAg negative, and HBV surface antigen (HBsAg) negative. In patients with a hepatitis B flare, the frequency of HBV core-specific TNF-α producing CD4 T cells was positively correlated with patients' ALT and total bilirubin levels, and the frequency of those cells changed in parallel with the severity of liver damage. Patients with HBeAg/HBsAg loss after flare showed higher frequency and dominance of HBV-specific IFN-γ producing CD4 T cells, compared to patients without HBeAg/HBsAg loss. Both the frequency and the dominance of HBV S-specific IFN-γ producing CD4 T cells were positively correlated with the decrease of HBsAg during flare. A differentiation process from TNF-α producing cells to IFN-γ producing cells in HBV-specific CD4 T cells was observed during flare. Eight and 9 HBV-derived peptides/pairs were identified as HLA-DRB1*0803 restricted epitopes and HLA-DRB1*1202 restricted epitopes, respectively. HBV-specific TNF-α producing CD4 T cells are associated with liver damage, while HBV-specific IFN-γ producing CD4 T cells are associated with viral clearance in patients with chronic HBV infection. TNF-α producing cells are the dominant population of hepatitis B virus (HBV)-specific CD4 T cells in patients with chronic HBV infection. This population of cells might contribute to the aggravation of liver damage in patients with a hepatitis B flare. HBV-specific IFN-γ producing CD4 T cells are associated with HBV viral clearance. Differentiation from HBV-specific TNF-α producing CD4 T cells into HBV-specific IFN-γ producing CD4 T cells might favor HBV viral clearance. [ABSTRACT FROM AUTHOR]

Monoclinic bismuth vanadate has been widely used as a promising n-type semiconductor for photoelectrochemical (PEC) water decomposition due to its high reserves, good stability in neutral solutions, and relatively narrow band gap. Here, we developed a simple method to prepare a thin NiOOH layer on the surface of BiVO 4 nanorod arrays. The heterostructured photoanode shows great enhancement for the photocurrent density of 2.7 mA cm−2 at 1.23 V vs. RHE, which is ~2.3 times higher than that of pristine BiVO 4 electrode, due to NiOOH as an efficient oxygen-releasing catalyst with abundant oxygen vacancies. The NiOOH/BiVO 4 photoanodes are systematically studied with X-ray diffraction, Raman, X-ray photoelectron spectra, scanning electron microscopy, transmission electron microscopy, and UV–vis diffuse-reflectance spectrum. The heterostructured photoanode shows excellent PEC activity, which can provide a promising and easy strategy to prepare such photoanode with high-efficient oxygen evolution co-catalysts. • An ultra-thin NiOOH layer on the surface of BiVO 4 was prepared. • The current density of NiOOH/BiVO 4 was 2.3 times higher than BiVO 4. • The NiOOH/BiVO 4 showed the ABPE of 0.68% at 0.8 V vs. RHE. • The NiOOH/BiVO 4 had super-duper PEC stability. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of magnetic metal on the absorption performance of metamaterial absorber (MMA), a dual-peak MMA based on magnetic metal nickel is designed and demonstrated in the P-band (300–1000 MHz). Two-layer square-ring-metal resonator arrays and two-layer dielectric substrates are arranged alternately with each other to constitute the proposed dual-peak MMA backed with a reflective metal plate. The influences of copper or nickel metallic layers on the absorption coefficients are comparatively analyzed. For the nickel MMA, the dual-peak absorption coefficients of 99.82% and 99.09% are achieved at 394 MHz and 605 MHz, respectively. Moreover, the thickness of dual-peak MMA could be reduced to 9 mm by employing magnetic metal nickel. The physical mechanism of dual-peak absorption is illustrated by surface current distributions, magnetic field distributions and power loss density distributions. The relationship between the changes of geometric dimensions and the shift of peak absorption frequencies is ultimately discussed. These results could provide instructive guidance for realizing a thin dual-peak MMA in the P-band. [ABSTRACT FROM AUTHOR]

Bismuth vanadate as photoanode with suitable bandgap and appropriate valence band positions is generally very stable in aqueous solution and cheap, but the photochemical activity is usually limited by poor electron mobility and low oxygen evolution kinetics. Herein, we exhibit that the above-mentioned problems can be solved by introducing a foreign dopant (Mo6+) into the BiVO4 film to create a distributed n+-n heterojunction and combining the BiVO4 photoanode with cobalt–phosphate water oxidation catalyst to improve the oxygen evolution kinetic. We systematically study the relationship between the higher photoelectrochemical performance and Mo-doping and cobalt–phosphate (CoPi) modification by XRD, Raman, SEM, TEM, LSV, EIS, I–t, and Mott–Schottky measurements, and the CoPi-Mo:BiVO4 heterojunction photoanode shows a current density of 3.27 times higher than that of pristine BiVO4 photoanode. Then, we concentrate our attention on a novel perspective for understanding the photoelectrochemical mechanism of interfacial charge transfer with the Mo-doping and CoPi modification on the BiVO4 photoanodes. This work provides new insights into the rational design of novel photoanodes from various improvement strategies with high photoelectrochemical performance and further utilization for environmental practical applications. [ABSTRACT FROM AUTHOR]

Electromagnetic parameters for a magnetic conductive hallow fiber have been derived, and the anisotropy of the magnetic permeability and the electric permittivity for a hollow fiber was demonstrated theoretically. The axial parameters μ// and &eh;// are the key factors related to electromagnetic characteristics of the hollow fiber. Simulations have been carried out to study the axial permeability μ//, and axial permittivity &eh;// of a magnetic conductive hallow fiber with different geometric, and electrical parameters such as diameter, aspect ratio and conductivity The simulations carried out reveal several interesting properties of the hallow fiber's electromagnetic parameters. (1) The parameters μ′//, μ″//, &eh;′// and &eh;″// all decrease with increasing outer radius from 0.5 to 6 µm. (2) When the aspect ratio of the hallow fiber is above 30 µm, μ′// and μ″// remain at constant, while, &eh;′// and &eh;″// are found to increase. (3) The parameters μ′//, μ″//, and &eh;′// all decrease with increasing conductivity, however &eh;″// increases with increasing conductivity. Additionally these simulated results are consistent with reported experimental results carried out on electromagnetically modified hollow carbon fibers. [ABSTRACT FROM AUTHOR]

Recently, researchers have proposed to leverage technology-supported data (log files) to investigate temporal and sequential patterns of interaction behaviors in learning processes. There are two major challenges to be addressed: clarifying the positioning of interaction levels and identifying the evolution of the interaction action patterns in learning processes, particularly for students with differing achievements. This paper explores the use of sequential pattern mining to address the evolution of student action patterns in Massive Private Online Courses (MPOCs) and compare these patterns between different achievement groups. The study was conducted with first-year undergraduate computer science students enrolled in a computer application course at a traditional open university in one of the Chinese provinces (N = 1375). The results showed the development of various action patterns in each phase of the course and the distinct action patterns for high-achieving and low-achieving students. The findings of study provide a new perspective for instructors and students to understand interaction patterns at the fine-grained level, and can help instructional designers develop learner-cantered courses and platforms to improve online learning. [ABSTRACT FROM AUTHOR]

[Display omitted] • We designed, synthesized and evaluated a series of highly effective PARP/CDK6 dual inhibitions. • P4i could effectively inhibit the proliferation of the three TNBC cells. • P4i could induce DNA damage in TNBC cells with wild-type BRCA. Inhibition of PARP is synthetic lethal with defects in BRCA, which provide effective targeted therapy strategy for BRCA mutation type of TNBC patients. However, approximately 80% of TNBC patients do not have BRCA mutations. Recent studies have shown that CDK4/6 inhibitors can increase the sensitivity of wild-type BRCA cells to PARP inhibitors. We designed a series of dual PARP and CDK6 inhibitors, and the most promising compound, P4i , showed good inhibitory activity against PARP1 and CDK6 and good inhibitory effects on MDA-MB-231 (IC 50 = 1.96 μM), MDA-MB-468 (IC 50 = 2.81 μM) and BT-549 (IC 50 = 2.37 μM) cells with wild-type BRCA. Compared with Olaparib, the inhibition capacity of the three BRCA wild-type (MDA-MB-231, MDA-MB-468 and BT-549) cells was about 10–20 times higher, and even better than the combination of Olaparib and Palbociclib. As a novel PARP multifunctional molecule, it is a potential compound for the treatment of BRCA wild-type TNBC. [ABSTRACT FROM AUTHOR]

• The infrared emissivity presents periodical fluctuation phenomenon along edge length. • The peaked frequency is inclined to shift towards lower region with area ratio increased. • There exists intrinsic attenuation which is probably attributed to the diffuse scattering. Composites or structures with adequate infrared reflection and microwave transmission are favorable from practical point of view. In this paper, oriented flaky aluminum filled pyramidal-frustum shaped periodic coatings was developed, and the effect of area of flaky aluminum powder filled coating on the infrared emissivity as well as microwave transmission behavior was intensively studied combined experiments with simulation. Results shown that the increments of oriented flaky aluminum filled coating could effectively reduce infrared emissivity. After spraying flaky aluminum filled periodic structures on the microwave absorbing material, the frequency corresponding to minimal reflection loss is inclined to shift towards lower frequency. Numerical simulation results shown that reflection coefficient gradually increases with increasing in frequency and area ratio of flaky aluminum filled coating. Besides, there exists intrinsic attenuation of flaky aluminum filled pyramidal-frustum shaped periodic coating, which is probably attributed to the diffuse scattering within step edge region. [ABSTRACT FROM AUTHOR]

Cutaneous squamous cell carcinoma (CSCC) remains the second most prevailing cancer worldwide and presents high mortality rates. Given that chemoresistance becomes an enormous obstacle to the therapy for CSCC patients, there is a pressing need to discover novel strategies for enhancing the response of CSCC cells to cisplatin. Emerging evidence has unfolded that miRNAs are participated in regulation of drug resistance in multiple cancers. MiR-3619-5p has been proofed to exert tumor inhibitive activities in human malignancies, but the biological function of miR-3619-5p in the progression of CSCC is still unclear. In this study, we observed that miR-3619-5p expression was pronouncedly dropped in cisplatin-resistant CSCC cells. Subsequently, miR-3619-5p was validated to act as a tumor suppressor in CSCC through retarding cell proliferation and cisplatin resistance. Besides, our findings certified that KPNA4 was highly expressed in cisplatin-resistant CSCC cells. Further, KPNA4 was negatively regulated by miR-3619-5p. Rescue experiments unveiled that KPNA4 counteracted the miR-3619-5p-mediated regulation of CSCC tumorigenesis. On the whole, miR-3619-5p inhibited cell proliferation and cisplatin resistance of CSCC by regulating KPNA4 expression, suggesting that miR-3619-5p/KPNA4 pathway may represent a potential promising strategy for the treatment of patients with CSCC. • MiR-3619-5p expression is pronouncedly dropped in cisplatin-resistant CSCC cells. • MiR-3619-5p suppresses cell proliferation and cisplatin resistance of CSCC cells. • KPNA4 is a target of miR-3619-5p in CSCC. • MiR-3619-5p hampers proliferation and cisplatin resistance in CSCC via KPNA4. [ABSTRACT FROM AUTHOR]

Prostate cancer (PCa) is the most common malignant tumor for men. But the mechanism is unclear. EIF3C was shown to be overexpressed in PCa tissues and cell lines. EIF3C overexpression was correlated to age and tumor stage in PCa patients and indicated poor survival. The proliferation, migration, and invasiveness of PC3 cells were all inhibited after EIF3C knockdown. Additionally, the phosphorylation level of PI3K and Akt was downregulated while total NF-κB and Myc decreased after EIF3C knockdown. But the expression of IκB increased reversely. Therefore, EIF3C at least partially regulates the activity of PI3K/Akt/NF-κB signaling pathway in PC3 cells. [ABSTRACT FROM AUTHOR]

The efficacy of the flipped classroom model largely depends on the specifications of its design and implementation, and one important specification to consider is student agency. With the purpose of prescribing the optimal level of student agency for the flipped classroom, this study conducted a repeated‐measures experimental design to compare the effects of three levels of student agency in an undergraduate flipped course with 43 students. The empirical results revealed that student agency had a significant impact on students' academic performance and perceived learning experience. Moreover, a low level of student agency appeared to induce superior performance and evaluation ratings from the students and counter the influence of personality and self‐study time. The findings are expected to inform the design and implementation of flipped courses and extend our understanding of student‐centred learning to the context of the flipped classroom. [ABSTRACT FROM AUTHOR]

Background: Adverse drug reactions (ADRs) are unintended and harmful reactions caused by normal uses of drugs. Predicting and preventing ADRs in the early stage of the drug development pipeline can help to enhance drug safety and reduce financial costs. Methods: In this paper, we developed machine learning models including a deep learning framework which can simultaneously predict ADRs and identify the molecular substructures associated with those ADRs without defining the substructures a-priori. Results: We evaluated the performance of our model with ten different state-of-the-art fingerprint models and found that neural fingerprints from the deep learning model outperformed all other methods in predicting ADRs. Via feature analysis on drug structures, we identified important molecular substructures that are associated with specific ADRs and assessed their associations via statistical analysis. Conclusions: The deep learning model with feature analysis, substructure identification, and statistical assessment provides a promising solution for identifying risky components within molecular structures and can potentially help to improve drug safety evaluation. [ABSTRACT FROM AUTHOR]

Pulmonary inflammation and progressive lung destruction are the major causes of chronic obstructive pulmonary disease (COPD), resulting in emphysema and irreversible pulmonary dysfunction. Heparin-binding EGF-like growth factor (HB-EGF), is known to play a protective role in the process of various inflammatory diseases. However, its effect on COPD is poorly understood. This study was designed to determine the effect of HB-EGF on lung inflammation and injury in a murine model of pulmonary emphysema. HB-EGF promoted percent survival and body weight, attenuated lung injury, inflammatory cells, and cytokines infiltration, and prevented lung function decline. Additionally, treatment of rHB-EGF suppressed the nuclear translocation of nuclear factor κB (NF-κB)/p65, decreased TUNEL-positive cells and the expression of caspase 3, and increased the expression of PCNA, HB-EGF, and EGF receptor (EGFR). We conclude that HB-EGF attenuates lung inflammation and injury, probably through the activation of EGFR, followed by suppression of NF-ΚB signalling, promotion of cell proliferation, and inhibition of apoptosis. [ABSTRACT FROM AUTHOR]

Previous studies indicate that vortex pairs over slender wings can produce time-averaged asymmetries even before the occurrence of vortex breakdown, but the sources for the asymmetries are still not clear. The present investigation uses numerical simulations and experimental measurements to explore the physical nature for the symmetry breaking of vortices. The results indicate that the time-averaged asymmetries come from a spatial growth of local disturbances (spatial instability) instead of a temporal instability. In numerical simulations, the time-averaged flows around a perfectly symmetric wing exhibit symmetric vortex pairs in which any asymmetric initial perturbation will decay and eventually converge to symmetric flows. However, if a geometric micro-perturbation is asymmetrically placed on the apex, asymmetric vortex pairs can be produced; downstream sectional perturbation energy grows spatially, and the growth rates increase with increasing angle of attack. The spatial perturbation growth mainly comes from antisymmetric modes, whereas symmetric modes have smaller growth rates. The experimental results indicate that artificial apex perturbations can overwhelm natural irregularities on the apex and dominate the orientations of asymmetric vortices. Unsteady aspects of the flows were also studied before vortex breakdown, with the emphasis put on oscillatory global modes by applying dynamic mode decomposition to the entire flow field. It was found that the most energetic modes are related to vortex shedding around trailing edges and instabilities of downstream shear layers, which has significant contributions to fluctuations of aerodynamic forces and moments. The vortex shedding exhibits strong three dimensionality characterized by oblique shedding and a beating phenomenon. [ABSTRACT FROM AUTHOR]

Functionalization of the C(sp3)−H bonds of trialkylamines is challenging, especially for reactions at positions other than the α position. Herein, we report a method for β‐C(sp3)−H allylation of trialkylamines. In these reactions, which involve synergistic borane/palladium catalysis, an enamine intermediate is first generated from the amine via α,β‐dehydrogenation promoted by B(C6F5)3 and a base, and then the enamine undergoes palladium‐catalyzed reaction with an allene to give the allylation product. Because the hydride and the proton resulting from the initial dehydrogenation are ultimately shuttled to the product by B(C6F5)3 and the palladium catalyst, respectively, these reactions show excellent atom economy. The establishment of this method paves the way for future studies of C−H functionalization of trialkylamines by means of synergistic borane/transition‐metal catalysis. [ABSTRACT FROM AUTHOR]

Functionalization of the C(sp3)−H bonds of trialkylamines is challenging, especially for reactions at positions other than the α position. Herein, we report a method for β‐C(sp3)−H allylation of trialkylamines. In these reactions, which involve synergistic borane/palladium catalysis, an enamine intermediate is first generated from the amine via α,β‐dehydrogenation promoted by B(C6F5)3 and a base, and then the enamine undergoes palladium‐catalyzed reaction with an allene to give the allylation product. Because the hydride and the proton resulting from the initial dehydrogenation are ultimately shuttled to the product by B(C6F5)3 and the palladium catalyst, respectively, these reactions show excellent atom economy. The establishment of this method paves the way for future studies of C−H functionalization of trialkylamines by means of synergistic borane/transition‐metal catalysis. [ABSTRACT FROM AUTHOR]

Recently, there has been a growing demand for ultra‐thin carbonized wood films (CWF) with high shielding efficiency (SE) to replace non‐renewable alternatives. Researchers aim to enhance electromagnetic (EM) wave absorption and improve electromagnetic interference (EMI) SE in CWF materials to reduce secondary pollution from reflected EM waves. In this work, the carbonized wood composite film (CWF/EP/Co) with a thickness of 120 µm through the process of hot‐pressing and carbonizing wood soaked in a mixed solution of water‐borne epoxy (EP) and Co/Zn‐MOF (ZIF‐67/8) is obtained. The CWF/EP/Co film exhibits excellent conductivity (105 S cm−1) and demonstrates an excellent EMI SE (73 dB) at a 200 µm thickness. Remarkably, the specific EMI shielding effectiveness (SSE/t) of CWF/EP/Co films reached 15833.3 dB·cm2·g−1 in the X‐band, making it the highest reported value among all wood‐derived EMI shielding materials. CWF/EP/Co films have a high absorption coefficient (A) of 0.4, indicating their effectiveness in absorbing EM waves. Furthermore, the EMI shielding effect of the large‐scale wallpaper (170 mm×170 mm) is confirmed by finite element analysis. Additionally, the CWF/EP/Co film exhibits good mechanical properties and effective Joule heating performance. This shielding film shows promise in applications such as buildings and smart homes, providing EMI shielding and warming effects. [ABSTRACT FROM AUTHOR]

Crop mapping is vital in ensuring food production security and informing governmental decision-making. The satellite-normalized difference vegetation index (NDVI) obtained during periods of vigorous crop growth is important for crop species identification. Sentinel-2 images with spatial resolutions of 10, 20, and 60 m are widely used in crop mapping. However, the images obtained during periods of vigorous crop growth are often covered by clouds. In contrast, time-series moderate-resolution imaging spectrometer (MODIS) images can usually capture crop phenology but with coarse resolution. Therefore, a time-series-based spatiotemporal fusion network (TSSTFN) was designed to generate TSSTFN-NDVI during critical phenological periods for finer-scale crop mapping. This network leverages multi-temporal MODIS-Sentinel-2 NDVI pairs from previous years as a reference to enhance the precision of crop mapping. The long short-term memory module was used to acquire data about the time-series change pattern to achieve this. The UNet structure was employed to manage the spatial mapping relationship between MODIS and Sentinel-2 images. The time distribution of the image sequences in different years was inconsistent, and time alignment strategies were used to process the reference data. The results demonstrate that incorporating the predicted critical phenological period NDVI consistently yields better crop classification performance. Moreover, the predicted NDVI trained with time-consistent data achieved a higher classification accuracy than the predicted NDVI trained with the original NDVI. [ABSTRACT FROM AUTHOR]

Due to the drastic aerodynamic heating effect in supersonic aircrafts, the operational performance of wave-transmitting dielectric ceramics functionalized radomes strongly depends on the temperature and oxidation. In this paper, the evolution of microwave dielectric responses in Si3N4 ceramics via gelcasting over a wide temperature range (25°C∼800°C) is investigated experimentally and theoretically. Specifically, the relative increment rate of real permittivity over evaluated temperature range is 4.46% at 8.2GHz and 8.67% at 12.4GHz, while the imaginary permittivity remains less than 0.06. Taking temperature-dependent polarized bound charge and damping coefficient into consideration, a revised dielectric relaxation model with Lorentz correction for Si3N4 ceramics has been established, which agrees well with evolution of experimental results. Furthermore, the best fitting results indicate that the activation energy of electrons Ea (15.46 ∼17.49 KJ/mol) is less than that of lattice Eb (33.29∼40.40 KJ/mol), which could be ascribed to the binding force between the electrons and nucleus is lower than covalent bonding force of lattice. Besides, excellent restorable feature of permittivity after heat-treatment lays a solid foundation for radome materials serviced in high temperature circumstances. [ABSTRACT FROM AUTHOR]

Building structure and other factors lead to the performance deterioration of global postioning system (GPS) positioning systems indoors. An adaptive model for Bluetooth-based indoor positioning is proposed in this paper, targeting at the complex indoor environment, to improve the performance of Bluetooth-oriented indoor positioning systems. More accurate Received Signal Strength Indicator (RSSI) calibration which is optimized via Gaussian filtering, together with the environment-dependent attenuation coefficient optimization, results in a more precise hybrid model in the complicated indoor environment. Experiment results show that the difference between the estimated results and the measured samples is less than 0.25m as the target node and reference node is less than 1.5m far from each other. As the distance increases to more than 1.5m, the relative difference between the estimated values and the measured ones decreases to 7.8% at most, satisfying the requirements for indoor positioning applications. [ABSTRACT FROM AUTHOR]

In this work, A ultrasonic assisted method was presented for etching and delaminating Ti 3 C 2 Mxene. With the help of ultrasonic cavitation, the process of etching in hydrofluoric acid (HF) was greatly shortened from 24 h to 4 h, and the delamination effectuated simultaneously. Delamination rate as high as 46% for mixture of delaminated Mxene flakes and accordion-like clay samples was achieved. [ABSTRACT FROM AUTHOR]

This study investigated the case-based method (CBM) instructional-design theory and its application in designing self-directed online instruction. The purpose of this study was to validate and refine the theory for a self-directed online instruction context. Guided by formative research methodology, this study first developed an online tutorial based on 13 design assumptions synthesized from the CBM literature. The researchers then formatively evaluated the online tutorial as a design instance of CBM through two iterations of design, evaluation, and revision. The major findings included: (1) perceived value of various CBM design features, (2) benefits and limitations of applying CBM in the tutorial design, and (3) validation and revision of a set of generic and context-specific CBM design assumptions. These findings extend our understanding of CBM to the context of self-directed online instruction and provide useful insights and practical guidance to inform instructional design practices. [ABSTRACT FROM AUTHOR]

In this paper, SiC nanofibers (SiCNFs) as multifunctional interphase were prepared on carbon fibers via catalysis chemical vapor deposition (CCVD) in order to improve the microwave absorption for carbon fiber reinforced silicon nitride (CFs/Si 3 N 4 ) composites. Experimental results indicated that the chemical compatibility between CFs and Si 3 N 4 matrix under high temperature could be effectively improved by incorporating SiCNFs interphase. Additionally, the dielectric responses and microwave absorbing performance of CFs/Si 3 N 4 composites are significantly influenced by the mass fraction of SiCNFs on CFs. An optimal reflection loss (RL) of −14 dB and 96% absorbing bandwidth (BW) of X-band could be achieved in the CFs/Si 3 N 4 composites with 8 wt% of SiCNFs. Furthermore, experimental points of permittivity in Cole-Cole plane are inclined to distribute on distinguishing circular arcs, corresponding to three types of electric polarization modes. It is concluded that the hopping relaxation of electrons between SiCNFs plays more pronounced contribution to the superior microwave attenuation capability of CFs/Si 3 N 4 composites with SiCNFs interphase than the relaxation loss of free electrons inside short CFs. [ABSTRACT FROM AUTHOR]

To get inside the properties of N,N-disubstituted Schiff bases, we synthesized three high-yielding benzaldehyde Schiff bases. We used the reaction between salicylaldehyde and different diamine compounds, including diamine, ethanediamine, and o-phenylenediamine, determining the structure of obtained molecules by nuclear magnetic resonance spectroscopy and electrospray ionization mass spectroscopy. We thus evaluated the microbicidal and antitumor activity of these compounds, showing that salicylaldehyde-hydrazine hydrate Schiff base (compound 1a) significantly inhibited the growth of S. aureus; salicylaldehyde-o-phenylenediamine Schiff base (compound 1c) displayed a strong capability to inhibit the proliferation of leukemia cell lines K562 and HEL. Moreover, we observed that the antibacterial action of 1a might be associated with the regulation of the expression of key virulence genes in S. aureus. Compound 1c resulted in a strong apoptotic activity against leukemia cells, also affecting the cell cycle distribution. Overall, our novel N,N-disubstituted Schiff bases possess unique antibacterial or antitumor activities that exhibit the potent application prospect in prophylactic or therapeutic interventions, providing new insights for developing new antibacterial and anticancer chemical agents. [ABSTRACT FROM AUTHOR]

The electromagnetic interference (EMI) shielding of dense Ti 3 AlC 2 ceramics with distinct microstructures were investigated up to 800 °C. Ti 3 AlC 2 exhibits high EMI shielding effectiveness (SE) around 30 dB which was mainly attributed to high electrical conductivity and complex permittivity. Besides, the EMI shielding were sensitive to the microstructure. Ti 3 AlC 2 with high aspect ratio grains and certain degree of texture were preferred for high SE indicating that the typical layered structure also contributes to the high shielding capability. These results indicate that layered Ti 3 AlC 2 ceramics could be considered as promising structural EMI shielding materials at high temperatures. [ABSTRACT FROM AUTHOR]

The high-temperature dielectric behavior of multilayer C f /Si 3 N 4 composites fabricated by gelcasting and pressuureless sintering was intensively investigated at temperatures coverage up to 800 °C in X-band (8.2–12.4 GHz). Experimental results have shown the permittivity of Si 3 N 4 matrix exhibits excellent thermo-stability with temperature coefficient lower than 10 −3 °C −1 . Besides, both the real and imaginary parts of permittivity of multilayer C f /Si 3 N 4 composites exhibit positive temperature coefficient characteristic which attributed to the enhancement of space charge polarization. Furthermore, temperature-dependent permittivity of C f /Si 3 N 4 composites is demonstrated to be well distributed on circular arcs with centers actually keep around the real ( ε ' ) axis in Cole-Cole plane. Finally, the relaxation time for multilayer C f /Si 3 N 4 composites gradually increases from 216.1 ps to 250.2 ps when heated from room temperature to 800 °C, and is almost twice as much as a single cycle for electromagnetic wave in X-band which leads to continuous decrease in permittivity with frequency. [ABSTRACT FROM AUTHOR]