Browse Articles

The migration of Σ3{112} incoherent twin boundary step in face-centered cubic metals under uniaxial loading

Pure steps such as Σ3{112} incoherent twin boundary (ITB) steps often present along the coherent twin boundary regardless of deformation or annealing twins in metals with a face-centered cubic (FCC) structure. Corresponding to the defect structure of Σ3{112} ITB step, this pure step is composed of multiple Shockley partial dislocations with a net zero Burgers vector. It is generally believed that such pure steps do not move under mechanical loading because of the zero Peach–Koehler force. Here, we demonstrate the migration of pure steps by atomistic simulations under uniaxial tension and reveal the driving force associated with elastic anisotropy, i.e., the driving force originates from an imbalance in the elastic strain energy density across the TBs. Therefore, we introduce a compliance anisotropy factor, calculated by density functional theory, to characterize the migration capability of the Σ3{112} ITB step in FCC metals.

Coaches’ insights: Determinants of athlete success, physical demands and training approaches in single-handed Olympic-class dinghy sailing

Gaining insights into experienced coaches’ perceptions and understanding of performance and training can enhance knowledge to optimise athlete performance. Ten experienced International Laser Class Association dinghy (ILCA) sailing coaches with world-class and elite ILCA coaching credentials undertook semi-structured interviews to explore three key topic areas: i) determinants of athlete success, ii) physical demands of competition, and iii) training practices and philosophies. Hierarchical content analysis was used to establish general dimensions and higher order themes from the interview transcripts. Three general dimensions were established within the topic area of determinants of athlete success: i) sailing the boat fast, ii) being a knowledgeable athlete, and iii) consistent execution. Within the topic area of physical demands of competition three general dimensions were also developed: i) hiking is the most physically demanding skill, ii) environmental conditions influence athletic demands, and iii) accumulation of fatigue over a regatta. Finally, in the topic area of training practices and philosophies there were two general dimensions: i) periodisation, and ii) specific training. Overall, hiking featured across all three topic areas, highlighting its importance in ILCA sailing. Additionally, ‘feel’ and ‘keeping the joy’ were identified as higher order themes that have been under-researched in current literature. Findings suggest coaches should target consistency in both on and off-water training through ‘keeping the joy’ and sailing in a variety of conditions to improve aspects such as ‘feel’ and ‘pattern recognition’. We provide key insights into components of performance and aspects of the physical demands and training in ILCA sailing to optimise athlete performance.

Harnessing sliding ferroelectricity for layer-polarized spin Hall effect in ZrX2 (X = Cl, Br, I) bilayers

Quantum layertronics investigates the interaction between the layer degree of freedom in 2D van der Waals materials and electron charge or spin, enabling innovative quantum device applications. Using first-principles calculations, sliding ferroelectricity is demonstrated for the ZrX2 (X = Cl, Br, I) bilayers. The moderate electric polarization (0.24–0.5 pC/m) and sliding energy barrier (11–18.8 meV/f.u.) values of ZrX2 bilayers indicate their suitability for low energy cost and high-speed data writing devices based on sliding ferroelectricity. With the effect of spin–orbit coupling, spin splitting occurs at the T-symmetry-connected valleys of the valence band, generating Berry curvature in the ZrX2 bilayer. When combined with sliding ferroelectricity, this effect leads to significant layer polarization with the layer splittings of 19, 23.5, and 46.7 meV for AB-stacked ZrCl2, ZrBr2, and ZrI2 bilayers, respectively. The coupling between out-of-plane ferroelectricity and electronic structure induces a layer-locked Berry curvature, giving rise to the layer-polarized spin Hall effect (LP-SHE) in bilayers. This LP-SHE is intimately linked to sliding ferroelectricity, allowing for reversible control through ferroelectric switching, making it an ideal candidate for 2D spintronic applications.

Relative age effect at Concacaf championships: Influence of sex, age, nationality, playing position, and playing status

Relative age effects in soccer are typified by an overrepresentation of players born earlier in the selection year. Examinations of relative age effects remain limited in female players and developing soccer nations. The aim of the present study was to examine the influence of sex, age, nation, playing position, and playing status in international level soccer players under Confederation of North, Central American and Caribbean Association Football (Concacaf). The sample consisted of a total of 1,959 active soccer players from 24 soccer nations that competed in recent Concacaf Championships. Results indicated an evident relative age effect in male [p < 0.05] but not female [p = 0.81] players. Male players were over‐represented by players born in the first quartile for the U17 [p < 0.01] level, however, this over‐representation did not transfer to the U20 or senior levels. No relative age effects were observed at any level for female players. A large proportion of nations demonstrated relative age effects in male, but not female samples. Relative age effects were shown for players participating at age group level, but not those ‘playing-up’. Results from this study highlight the continued disparity in relative age effects prevalence between male and female players raises further questions regarding the value of selecting relatively older players to metrics of success, transition, and selection for senior international soccer. This information can be used to advance talent identification and development in Concacaf nations.

Magnetic field-controlled nanoscale spin-wave vertical directional coupler

The directional coupler is a fundamental element of wave-based circuits. The state of the art for the spin-wave directional couplers consists mostly of macroscopic waveguides or two-dimensional planar systems. In this Letter, we present the design of the nanoscale spin-wave vertical directional coupler with a very high efficiency exceeding 99.5%. We demonstrate that the operation of the coupler can be controlled by the magnitude of the external magnetic field. Moreover, it can perform multiplexing and demultiplexing of the spin-wave signal. Such a device ought to become an essential element of the three-dimensional magnonic circuits.

Enhancing corn industry sustainability through deep learning hybrid models for price volatility forecasting

The fluctuations in corn prices not only increase uncertainty in the market but also affect farmers’ planting decisions and income stability, while also impeding crucial investments in sustainable agricultural practices. Collectively, these factors jeopardize the long-term sustainability of the corn sector. In order to address the challenges posed by maize price volatility to the sustainability of the industry, this study proposes a multi-module wavelet transform-based fusion forecasting model: the TLDCF-TSD-BiTCEN-BiLSTM-FECAM (TLDCF-TSD-BBF) model, which is capable of accurately predicting short-term maize price volatility, thereby enhancing the sustainability of the industry. The model integrates a three-layer decomposition combined dual-filter time-series denoising method (TLDCF-TSD), a bidirectional time-convolutional enhancement network (BiTCEN), a bidirectional long- and short-term memory network (BiLSTM), and a frequency-enhanced channel attention mechanism (FECAM) to improve prediction accuracy and robustness. First, TLDCF-TSD is used to decompose the corn price time series into multiple scales, effectively separating the frequency components, extracting the signal details and trend information, and reducing the data complexity and non-stationarity. Secondly, BiTCEN designed in this paper effectively captures the short-term dependencies in the corn price data through the unique bidirectional structure and the special hybrid convolutional structure, and then accurately extracts the local features of the data, while BiLSTM mines the long-term trends and complex dependencies in the data by exploiting its bidirectional processing and long-term memory capabilities. Finally, FECAM enhances the focus on key temporal features in the frequency domain by grouping the input features along the channel dimensions and applying discrete cosine transform to generate attention vectors, improving the prediction accuracy and robustness of the model. The dataset utilized in this study was sourced from the BREC Agricultural Big Data platform, ensuring the reliability and accuracy of the corn price data for our analysis. This study utilizes price data from China’s five major corn-producing regions as a case study to demonstrate the efficacy of the proposed model in corn price forecasting. Through extensive experimentation, it has been established that the model significantly outperforms existing baseline models across various evaluation metrics. To be more specific, when dealing with different datasets, its MAE values are 0.0093, 0.0137, 0.0081, 0.0055, and 0.0101 respectively; the MSE values are 0.0002, 0.0002, 0.0001, 0.0001, and 0.0002 respectively; the MAPE values are 1.3630, 1.7456, 1.1905, 0.8456, and 1.7567 respectively; and the R2 values are 0.9891, 0.9888, 0.9943, 0.9955, and 0.9933 respectively. These data fully demonstrate the excellent performance of this model.

Shining light in a heartbeat: Controlling cardiac bioelectricity with membrane-targeted photoswitches

The heart's rhythmic contractions are driven by bioelectric signals that coordinate the excitation and propagation of action potentials throughout the cardiac tissue. Maintaining precise control of this rhythm is essential for proper heart function and preventing life-threatening conditions. Traditionally, this regulation has relied on pharmacological interventions, tissue ablation, or electric shock delivery. However, these methods often come with off-target effects, tissue damage, and high energy demands. Optostimulation presents a promising alternative, offering highly precise and minimally invasive control with significantly fewer side effects. In this Perspective, we explore current light-based technologies designed to modulate cardiac bioelectricity, with a particular focus on an innovative approach based on sarcolemma-targeted photoswitches. Finally, we discuss the main translational opportunities and critically examine the key challenges that must be addressed to transition this technology from basic research to clinical application.

Effect of emancipative values on life satisfaction across different levels of democracy: A cross-national analysis of the World Values Survey

Emancipative values – advocating for personal freedoms, equality, and autonomy – are theorized to enhance life satisfaction by fostering empowerment and opportunities. The current study tested whether their impact is context-dependent, influenced by societal norms and institutional frameworks. We used data from wave seven of the World Values Survey (WVS) and the Varieties of Democracy (V-Dem) dataset, covering diverse countries and time periods. We examined the interaction between emancipative values and a country’s level of liberal democracy on life satisfaction using a random effects model accounting for country-level variations (random intercept and slope). The model was adjusted for individual-level variables, such as settlement size, income, and educational attainment, as well as country-level factors like lagged income per capita and regional affiliation. This approach allowed us to investigate the direct effect of emancipative values across different democratic contexts. Our final dataset included N = 76,702 participants across 58 countries. Countries with the highest levels of liberal democracy were also the most economically prosperous. Individuals in democratic nations were older, resided predominantly in larger settlements, demonstrated the highest levels of educational attainment, reported the highest incomes, and expressed the strongest adherence to emancipative values. Our random effect model revealed a negative main effect of emancipative values on life satisfaction. A significant positive interaction between democracy and emancipative values was also identified. Less democratic countries demonstrated a negative effect of emancipative values while no significant effect was observed in more democratic contexts. Overall, our study challenges the notion that emancipative values universally enhance life satisfaction, highlighting the significance of cultural and institutional congruence in assessing how personal values affect well-being. These findings emphasize the importance of considering contextual factors when examining the relationship between individual values and life satisfaction across diverse political and cultural landscapes.

Separated reversal of spins in two spin sublattices and strong microwave absorption with adjustable broad bandwidth in SrFe10.4Zn0.8Sn0.8O19

The dynamical spin resonance stores a large amount of electromagnetic energy. Usually, it is a collective response of all exchange coupled spins. We observed two distinct spin resonances due to two spin sublattices in SrFe10.4Zn0.8Sn0.8O19 sintered at 1300 °C for 6 h. The magnetocrystalline anisotropy ratio of the two spin sublattices is 2. Other SrFe10.4Zn0.8Sn0.8O19 sintered for longer or shorter than 6 h have consecutive resonances. Their antiferromagnetic interaction in the sublattices helps the spins rotate coherently. The separated spin resonances store more magnetic energy than the consecutive one. The sample sintered for 6 h has the highest absorption coefficient, and the absorption bandwidth (RL≤−10 dB) is ≥ 8.35 GHz above 9.65 GHz at a thin thickness of 1.6 mm. As SrFe10.4Zn0.8Sn0.8O19 is sintered at 1400 °C, the microwave absorption is adjusted to be broader than 13.5 GHz from 4.5 to 18+ GHz, covering the C-, X-, and Ku-bands, making SrFe10.4Zn0.8Sn0.8O19 sintered at both conditions very attractive microwave absorbing materials.

Medicine’s rapid adoption of AI has researchers concerned

TempODEGraphNet: predicting user churn using dynamic social graphs and neural ODEs

Research on user churn prediction has been conducted across various domains for a long time. Among these, the gaming domain is characterized by its potential for diverse types of interactions between users. Due to this characteristic, many studies on churn prediction have considered the relationships between users and have primarily applied social network analysis. Recently, the use of Graph Neural Networks (GNNs) has been actively applied. However, existing studies utilizing GNNs have limitations as they use static graphs that do not effectively capture the dynamic nature of interactions that change over time. This study addresses these limitations by proposing a dynamic graph model for predicting user churn in games based on user interactions. Data are sourced from 10,000 users of ’Blade & Soul’ by NCSOFT. The proposed model effectively captures changes in user behavior over time and predicts user churn with a focus on interactions among users. Experimental results reveal that the proposed model achieves a higher F1 score compared with conventional algorithms and static graph models. Dynamic graphs more accurately reflect changes in user behavior compared with static graphs, particularly in domains with active interactions such as massively multiplayer online role-playing games. This work highlights the significance of user churn prediction in the gaming industry and demonstrates the effectiveness of the predictive models that use dynamic graphs.

Tailoring organic emission using dual nanocavities in planarized photonic crystal structure

This study investigates the feasibility of tailoring organic emission profiles using adjacent nanocavities in a planarized photonic crystal, a concept that holds potential for practical photonic devices. The photonic crystal, made of silicon nitride, is fabricated on a SiO2/Si substrate. The holes of the photonic crystal are filled with spin-on-glass, and an organic emissive layer is deposited on top. Despite the narrowing of the photonic bandgap due to the planarization, a sharp emission peak with a quality factor of approximately 400 is observed in micro-photoluminescence measurements, attributed to the careful design of nanocavities. Furthermore, we investigate the influence of a nearby nanocavity through simulations and experiments. It is observed that two cavities can operate independently, even at smaller inter-cavity distances, by detuning their resonant wavelengths. This capability facilitates the dense and scalable integration of nanocavities for future applications.

Daily briefing: ‘A necessary evil’ — Cutting off rhinos’ horns to deter poachers really works

A teacher-led classroom intervention in an area of Mexico experiencing community violence: A controlled mixed-method feasibility study

Objectives We aimed to explore the effectiveness of a daily ten-minute teacher-led group thought field therapy stress-reduction intervention on middle-school adolescents residing in an area experiencing high levels of interpersonal and community violence. We hypothesized that it would lead to a reduction of trauma symptoms and improve grades in reading and math. Methods In this double-masked feasibility study, adolescents in one school received a daily teacher-led thought field therapy intervention, and children in a different school served as an active waitlist group and received the same amount of time in a daily unguided drawing activity. The schools were geographically distant to prevent cross-contamination. Results Due to differences between groups in PTSD and academic performance prior to intervention, differences within each school’s scores over time were calculated and compared to each other for indirect assessment of effect. PTSD scores at the treatment school showed no lasting change at five months, while the control school showed moderate improvement. Adolescents in the treatment group demonstrated large improvements in both reading and math. Adolescents in the control group demonstrated moderate decrease in math, and no change in reading. Conclusions Preliminary evidence gained in this study suggests that a teacher-led ten-minute group thought field therapy exercise might assist adolescents’ learning in reading and math. However, in an area experiencing ongoing interpersonal and community violence, a more multicomponent approach with longer periods of intervention, caretaker involvement and individual therapy for those who might benefit from it, may be needed. Study registration number: ISRCTN10548974.

Resonant control of magnetization in a shunted φ0 junction with LC circuit

The possibility of resonant control of magnetization in a Josephson superconductor–ferromagnet–superconductor φ0 junction shunted by an LC circuit is demonstrated. As a result of the resonance of Josephson oscillations with oscillations in the circuit, a time-independent superconducting current arises in the junction. Due to the coupling of the Josephson phase and the magnetization of the ferromagnetic layer, the resulting superconducting current leads to a deviation of the easy axis from its initial position and to a precession of the magnetization around the tilted axis. We show that the tilt value increases with increasing spin–orbit interaction and the Josephson to magnetic energy ratio. An analytical expression for the magnetization tilt is obtained, which agrees well with the results of numerical calculations. The emerging possibility of resonant control of magnetization in a shunted φ0 junction can be used in the development of prospective technologies in the field of superconducting electronics and spintronics.

Assessing adherence to physical activity guidelines and correlates among older Korean adults with a focus on 10-minute bout duration using subjective and objective measures

Background Understanding physical activity (PA) patterns in older adults is crucial for effectively promoting adherence to PA guidelines. However, measuring PA can be challenging because it involves a balance between ease of administration and accuracy of data collection. The primary objective of this study was to analyze PA levels in older Korean adults using both self-reported and objective accelerometer measures, and the secondary objective was to investigate the factors associated with adherence to PA guidelines. Methods Using data from the Korea National Health and Nutrition Examination Survey (KNHANES VII-2) 2017, we assessed 425 older adults who provided both self-reported and accelerometer data. Adherence to PA guidelines was evaluated using two different thresholds for the accelerometer data, each applied both strictly and with a tolerance of one to two minutes when defining a 10-minute bout. Results Self-reported data indicated a 34% adherence rate, whereas accelerometer-based rates ranged from 16% to 62.8%, depending on the cutoff values and tolerance settings. Bland-Altman analyses demonstrated notable differences between subjective and objective measurements. In terms of correlates, the questionnaire data highlighted factors such as education and household income, whereas the accelerometer-based findings emphasized sex, age, hypertriglyceridemia, and low high-density lipoprotein cholesterol. Conclusions This study revealed substantial discrepancies in both moderate-to-vigorous PA adherence estimates and significant predictors when comparing self-reported surveys to accelerometer data among older adults. For estimating population-level adherence, in the absence of accelerometer cutoff values established by a specialized lab, both self-reported data and accelerometer measurements offer unique insights. Meanwhile, when analyzing the factors influencing PA adherence, accelerometer data may be preferable, as subjective biases in self-report can affect the observed correlates in statistical results.

A hexagonal phase of BiCuTeO films: Growth, crystal structure, and thermoelectric properties

In this work, a stable metallic phase of BiCuTeO has been identified in c-axis oriented films. Unlike the tetragonal structure observed in BiCuTeO bulks, this film exhibits a unique hexagonal layered structure, consisting of alternating Bi2O2 layers and Cu2Te2 layers along the c-axis, with lattice parameters of c = 12.45 Å and a = b = 4.3 Å. A potential crystal structure model for this hexagonal phase has been constructed using first-principles simulations. Calculations of the phonon spectra and electronic band structures confirm the validity of the hexagonally symmetric structure as well as its metallic nature. Due to its lower resistivity and appropriate Seebeck coefficient, the hexagonal BiCuTeO film achieves a power factor of 3.4–7.7 μW cm−1 K−2 within the temperature range of 300–600 K.

Dolce vita: a four-step guide to stress-free holidays from academia

Development and validation of the pesticides label (pictograms and color codes) questionnaire: A pilot study of farmers’ understanding and practices in Lebanon

Farmers’ comprehension of color codes and pictograms of pesticides is crucial for ensuring the safe and effective use of these agricultural chemicals. These visual aids provide essential information about hazards, proper handling, and application methods. This understanding helps prevent accidents, protect health, and promote sustainable farming practices. This study aims to develop and validate a Pesticide Label Questionnaire (PLQ) qualitatively and quantitatively using psychometric measures to evaluate farmers’ comprehension of pictograms and color codes as well as the technical sign-related practices in Lebanon. The questionnaire, consisting of 29 statements, was generated and developed by experts in the field of agriculture, chemistry, environmental health, public health, and statistics. Face, content, and construct validity were assessed, and psychometric properties were examined for data validation. Internal consistency and reliability were measured using Cronbach’s alpha (α) and Guttman’s Lambda Coefficient. Statistical analyses were performed using Statistical Package for the Social Sciences (SPSS version 27) and RStudio (Version 1.1.456, Inc., 2009–2018). The Construct Validity analyses demonstrated strong reliability and coherence within the questionnaire, with an overall Cronbach’s alpha of 0.873. Section I (“Pictorial and Color Code Comprehension”) achieved a Cronbach’s alpha of 0.849, while section II (“Technical Sign-related Practice Assessment”) showed moderate reliability at 0.667. Factor analyses revealed a well-defined structure, with five components explaining 62.03% of the variance in section I and three components accounting for 61.81% in section II. These results highlight the questionnaire’s robust construct validity and its ability to capture key dimensions of comprehension and practice related to pesticide labels. The results of this study indicate that the 29-item PLQ is a valid and reliable tool for evaluating farmers’ understanding of pictograms and color codes along with technical sign-related practices.

Time-resolved nanosecond magnetization switching induced by spin-transfer torque for cryogenic memories

Spin-transfer torque magnetic random access memory (STT-MRAM) has emerged as a promising candidate for cryogenic data storage, owing to its nonvolatility, high density, low power consumption, and especially its nanosecond writing speed. However, the temperature dependence of the dynamics of its writing process remains unclear, hindering further optimization. Here, we investigate nanosecond STT switching dynamics in perpendicular magnetic tunnel junctions using time-resolved measurements from room temperature down to 10 K. We find that both the incubation time and the transition time exhibit certain temperature dependence, indicating that thermal effects influence not only the nucleation process preceding reversal but also the subsequent domain wall motion. Especially, the incubation time exhibits strong temperature dependence in the thermally activated regime, consistent with enhanced thermal assistance for nucleation at higher temperatures. In contrast, the incubation time becomes less temperature dependent in the precessional regime, reflecting a transition to a more deterministic switching behavior. These findings offer valuable insight into the switching dynamics and benefit the optimization of STT-MRAM performance in cryogenic memory applications.