Browse Articles

PyLRO: A Python calculator for analyzing long-range structural order

We present PyLRO, an open-source Python calculator designed to detect, quantify, and display long-range order in periodic structures. The program’s design methodology, workflow, and approach to order quantification are described and demonstrated using a simple toy model. Additionally, we apply PyLRO to a series of metastable AlPO4 structural intermediates from a prior high-pressure study, demonstrating how to compute and visualize structural order in all directions on a Miller sphere. We further highlight the program’s capabilities through a high-throughput analysis of structural patterns in the pressure-induced amorphization of AlPO4, revealing atomistic insights into specific energy regions of massive amorphous structures. These results suggest that PyLRO can be a valuable tool for investigating crystal–amorphous transition in materials research.

Artificial intelligence and network science as tools to illustrate academic research evolution in interdisciplinary fields: The case of Italian design

In this paper, we explore the application of Artificial Intelligence and network science methodologies in characterizing interdisciplinary disciplines, with a specific focus on the field of Italian design, taken as a paradigmatic example. Exploratory data analysis and the study of academic collaboration networks highlight how the field is evolving towards increased collaboration. Text analysis and semantic topic modelling identified the evolution of research interest over time, defining a ranking of pairs of keywords and three prominent research topics: User-Centric Experience Design, Innovative Product Design and Sustainable Service Design. Our results revealed a significant transformation in the field, with a shift from individual to collaborative research, as evidenced by the increasing complexity and collaboration within groups. We acknowledge the limitations faced by this work, suggesting that the methodology may be primarily suitable for bibliometric and more silos-like disciplines. However, we emphasize the urgency for the scientific community to address the future of research not indexed by large open-access databases like OpenAlex.

The Peierls stress of interfacial dislocation under lattice mismatches

The dislocation motion at heterointerfaces can be quantitatively predicted by estimating the Peierls barrier using the generalized stacking-fault energy surface. A simple formula is derived for the Peierls stress of misfit dislocations within the framework of the Peierls–Nabarro mechanism. This formula clarifies the correlation between a material’s yield strength, its elastic constant, and the dislocation structure, which is crucial for understanding the stability of heterointerfaces. Using the BAs/AlN heterojunction as an example, the validity of the energy barrier at the B–Al interface is confirmed through numerical results obtained from first-principles simulations.

Impact of communication anxiety on L2 WTC of middle school students: Mediating effects of growth language mindset and language learning motivation

Previous research has shown a connection between communication anxiety and willingness to communicate (WTC) among English as a foreign/second language (L2) learners. Nonetheless, the potential mediating roles of learners’ beliefs like growth language mindset and language learning motivation have not been thoroughly investigated, particularly in the context of middle school language learners. This study aimed to explore the relationship between communication anxiety and L2 WTC by considering the mediating roles of growth language mindset and language learning motivation. To achieve this goal, an online survey was administered to 847 participants from five middle schools in eastern China. Structural equation modeling was employed to analyze the collected data. The findings revealed that L2 WTC was negatively impacted by communication anxiety and growth language mindset, while positively influenced by language learning motivation. Additionally, communication anxiety had a negative effect on both growth language mindset and language learning motivation, whereas growth language mindset exerted a positive effect on language learning motivation. Moreover, either individually or synergistically, growth language mindset and language learning motivation played mediating roles in the relationship between communication anxiety and L2 WTC. These research findings have significant implications for understanding the interrelationship among the variables, offering an innovative perspective on the mediating effects of growth language mindset and language learning motivation on communication anxiety and WTC among secondary school students. Consequently, this study provides valuable insights for language learning and instruction among middle school students and teachers.

Two-carrier model-fitting of Hall effect in semiconductors with dual-band occupation: A case study in GaN two-dimensional hole gas

We develop a two-carrier Hall effect model-fitting algorithm to analyze temperature-dependent magnetotransport measurements of a high-density (∼4×1013cm−2) polarization-induced two-dimensional hole gas (2DHG) in a GaN/AlN heterostructure. Previous transport studies in GaN 2DHGs have reported a twofold reduction in 2DHG carrier density when cooled from room to cryogenic temperature. We demonstrate that this apparent drop in carrier density is an artifact of assuming one species of charge carrier when interpreting Hall effect measurements. Using an appropriate two-carrier model, we resolve light hole (LH) and heavy hole (HH) carrier densities congruent with self-consistent Poisson-k⋅p simulations and observe an LH mobility of ∼1400 cm2/Vs and HH mobility of ∼300 cm2/Vs at 2 K. This report constitutes the first experimental signature of LH band conductivity reported in GaN.

Correction to Supporting Information for Le et al., Motor neuron disease, TDP-43 pathology, and memory deficits in mice expressing ALS–FTD-linked <i>UBQLN2</i> mutations

Exploring cooking fuel choices among Ghanaian women of reproductive age: A socio-economic analysis from a statistical mechanics perspective

Access to clean and efficient cooking fuel is crucial for promoting good health, safeguarding the environment, and driving economic growth. Despite efforts to promote the adoption of cleaner alternatives, traditional solid fuels such as charcoal and firewood remain prevalent in Ghana. In this study, we utilized a statistical mechanical model as a framework to explore the statistical relationship between socio-economic factors such as educational attainment, wealth status, place of residence, and cooking fuel choices. We analysed data from the Ghana Malaria Indicator Survey (GMIS) conducted in 2019, involving a total of 2,942 women of reproductive age. The findings revealed that 13.77% of participants preferred using LPG fuels for cooking, while 86.23% preferred non-LPG fuels for their cooking needs. The data indicated that among LPG users, 96.54% are educated women of reproductive age, and 3.46% are non-educated women of reproductive age. Among these, 95.31% are non-poor, and 4.69% are poor. Additionally, 21.73% reside in rural areas, while 78.27% live in urban areas. The data also showed that among non-LPG fuel users, 68.70% are educated women of reproductive age, and 31.30% are non-educated women of reproductive age. Among this group, 16.04% are non-poor, and 83.96% are poor. Furthermore, 67.24% reside in rural areas, and 32.76% live in urban areas. Our findings showed that in the absence of social interaction, a woman’s wealth status has a relationship to her choice of fuel for cooking. Additionally, women of reproductive age in rural areas with some education demonstrated a significant private incentive (40.12%) to use LPG, implying a positive correlation between education and the use of LPG for cooking. However, when social interactions are considered, factors such as education, wealth status, and place of residence have significant relationships with a woman’s decision about fuel choice. The interaction strength among women of reproductive age in urban areas with some education shows a negative estimate (-4.06%), suggesting that there is no significant imitative effect. The study further suggests that urban women of reproductive age who are poor exert a greater influence on their urban counterparts who are not poor when social interaction is incorporated. Women of reproductive age in rural areas with some form of education exert a greater influence on women of reproductive age in rural areas with no form of education. We recommend that the government of Ghana and its stakeholders focus on leveraging the influence of urban poor women and educated rural women through community-led programs and educational campaigns. Financial support mechanisms like microfinance and subsidies, alongside reliable LPG infrastructure, can make access easier for these target groups. Tailored communication strategies, peer-to-peer learning, and collaboration with local institutions are crucial for spreading awareness and encouraging the adoption of LPG.

High performance triboelectric nanogenerator by synchrotron x-ray assisted Ru/g-C3N4 nanostructure incorporated into PDMS matrix

The integration of metal–semiconductor nanostructures is of significant interest to the advanced technology development. However, the synthesis methods for metal–semiconductor nanostructures are complicated and require multi-stage processing, which includes the separate synthesis of metallic and semiconductor nanostructures, controlling pH, and dedicated equipments. Herein, we report a one-step in situ synthesis and simultaneous embedding of Ru nanostructures on g-C3N4 nanosheets using the synchrotron x-ray irradiation method. The results indicate that Ru nanostructures were uniformly embedded within the g-C3N4 nanosheets, leading to the formation of Ru—O, RuO2, and Ru—O—Ru chemical bonds. Moreover, three distinct types of Ru nanostructures could be achieved by adjusting the x-ray dose. High-performance triboelectric nanogenerators (TENGs) were fabricated using these three types of Ru-embedded g-C3N4 nanosheets within a PDMS matrix. The output performance of these TENG devices was compared with that of PDMS and g-C3N4/PDMS TENGs. The improved dielectric constant contributes to the high performance of the TENG. The synthesized Ru/g-C3N4 nanostructures are notably significant due to increased contact surface area, charge distribution density, and the formation of a metal–semiconductor heterostructure system. These characteristics lead to high charge transfer rates, improved charge transport, and a higher density of charge trapping centers within the insulating matrix. Thus, we achieved a high TENG peak power density of 4.86 W/m2 during the contact separation process. The practical applicability of the TENG is also demonstrated. Furthermore, a 47 μF capacitor could be charged to 7.8 V in ∼400 s and can be used to continuously drive low power electronic gadgets.

Assessing the global dynamics of Nipah infection under vaccination and treatment: A novel computational modeling approach

In biology and life sciences, fractal theory and fractional calculus have significant applications in simulating and understanding complex problems. In this paper, a compartmental model employing Caputo-type fractional and fractal-fractional operators is presented to analyze Nipah virus (NiV) dynamics and transmission. Initially, the model includes nine nonlinear ordinary differential equations that consider viral concentration, flying fox, and human populations simultaneously. The model is reconstructed using fractional calculus and fractal theory to better understand NiV transmission dynamics. We analyze the model’s existence and uniqueness in both contexts and instigate the equilibrium points. The clinical epidemiology of Bangladesh is used to estimate model parameters. The fractional model’s stability is examined using Ulam-Hyers and Ulam-Hyers-Rassias stabilities. Moreover, interpolation methods are used to construct computational techniques to simulate the NiV model in fractional and fractal-fractional cases. Simulations are performed to validate the stable behavior of the model for different fractal and fractional orders. The present findings will be beneficial in employing advanced computational approaches in modeling and control of NiV outbreaks.

Application of the Skanavi model to CaCu3Ti4O12 materials

In this paper, the optical and static permittivities of CaCu3Ti4O12 supercells are calculated based on the Skanavi model by decomposing the electric field of molecules into the electric field of ions. The results show that the Skanavi model's theoretical predictions are significantly more accurate than those of the Clausius–Mossotti equation and Born model and are in good agreement with the experimental data. In addition, the absence of ferroelectricity in CaCu3Ti4O12 is also revealed by investigating the changes in the structural coefficients of the effective electric field caused by the displacement of Ti4+ along the z-axis. Finally, by analyzing the contribution of TiO6 octahedra or CuO4 planar squares to the static permittivity, the main polarization unit in the structure of CaCu3Ti4O12 has been discovered. This study not only makes up for the insufficient research on the polarization mechanism of CaCu3Ti4O12 but also provides a new tool to explore the polarization mechanism of other materials.

Correction for Orellana et al., Childhood maltreatment influences adult brain structure through its effects on immune, metabolic, and psychosocial factors

Computational and experimental approaches to explore defense related enzymes conferring resistance in Fusarium infected chilli plants by regulating plant metabolism through nutritional products

Nutritional status being the first line of defense for host plants, determines their susceptibility or resistance against invading pathogens. In recent years, the applications of plant nutrient related products have been documented as one of the best performers and considered as alternatives or/and supplements in plant disease management compared to traditional chemicals. However, knowledge about application of plant nutrient related products for the management of destructive fungal pathogen Fusarium oxysporum f.sp. capsici and their impact on the components of the antioxidant defense system, especially in chilli plants, still needs to be discovered. Therefore, in this current study, we aimed to evaluate two nutrient fertilizers viz. Krystafeed and Micro Plus at three different concentrations by soil drenching method for their effects against the Fusarium wilt of chilli and investigate the components of the antioxidant defense system of chilli plants. Correlation and computational analysis on the components of antioxidant defense system in various pathways were performed to predict the suitable binding sites of mineral ions. Results indicated that the combination of Krystafeed and Micro Plus was found the most effective with (27.01, 26.59%) disease incidence, followed by Micro Plus (29.56, 32.35%) and Krystafeed (38.21, 41.15%), both in greenhouse and field conditions, respectively. Moreover, the combination of Krystafeed and Micro Plus significantly increased the concentration of SOD (27.53, 108.96)%, POD (37.29, 45.65)%, CAT (19.33, 95.33)%, H2O2 (22.13, 118.98)%, TPC (27.39, 17.37)%, chlorophyll a (21.80, 35.74)%, chlorophyll b (57.57, 18.25)%, total chlorophyll (30.21, 19.83)%, Tocopherol (13.08, 33.66)%, TrxR (5.03, 36.56)%, MDA (13.84, 54.79)%, ascorbate (4.72, 17.28)%, Proline (5.94, 59.31)%, and phytoalexin (Capsidiol) (11.33, 55.08)% in the treated plants of resistant and susceptible chilli varieties, respectively, as compared to the untreated plants. Pearson’s correlation heat-map analysis showed that all the enzymes of antioxidant defense system were found positively correlated with each other. It is concluded that the improvement of crop resistance by the application of plant nutrient related products may be viable alternatives to synthetic chemicals for managing Fusarium wilt disease of chilli and potentially other pathogens.

Effect of electron–electron interactions on the emission characteristics of ultracold, nanoscale photoemission-based electron sources

For nearly 60 years, cold field emitters have been the source of choice for electron microscopy due to their high brightness and relatively low energy spread. In this paper, we have examined an alternative: nanoscale electron sources based on near-threshold photoemission. While these sources have not yet been realized, they hold the potential to produce significantly brighter beams than cold field emitters. We model electron–electron Coulomb interactions in beams emitted from such sources to calculate the impact of these interactions on the brightness and the energy spread. Our results show that these sources can theoretically deliver more than an order of magnitude brighter electron beams compared to cold field emitters along with more than an order of magnitude smaller energy spread, before being limited by the Coulomb interactions. Electron sources with such high brightness and low energy spread would be transformational for electron microscopy, enabling electron energy loss-based vibrational spectroscopy at the sub-nanometer scale.

Multidimensional well-being and income inequality in Central and Eastern Europe: A comparative analysis of CEE North and CEE Continental countries

Central Eastern European countries (CEEc) are characterized both by huge diversity in income inequality and, on average, by lower levels of well-being than in the other European Union (EU) countries. Given that income inequality may affect well-being negatively, the present study aims to explore the links between income inequalities and different dimensions of well-being in the eight CEEc, i.e. Poland, Czech Republic, Slovakia, Slovenia, Hungary, Latvia, Lithuania, and Estonia. The analysis is conducted in the two groups of CEEc regarding low and high inequality in income distribution, namely CEE Continental group and CEE North group (corresponding to post-socialist corporatist and post-socialist liberal, respectively). The multidimensional concept of well-being is applied, enabling deep exploration of its links with income inequalities in the following dimensions: subjective well-being (happiness) and objective well-being (material, health, educational, and environmental dimensions). We estimate the vector autoregression (VAR) models based on annual data disaggregated into quarterly data covering 2004 to 2020. The empirical results of Granger causality testing, which was used to investigate the links between income inequality and multidimensional well-being, indicated that not only are there differences between the groups in the studied patterns of interconnectedness, but also the groups of CEE North and CEE Continental countries are not homogeneous in those links.

Room-temperature ferromagnetism of chromium-doped molybdenum disulfide synthesized via chemical vapor deposition

Two-dimensional (2D) magnetic materials offer promising prospects for applications in magnetic storage and spin field-effect transistors. However, the inherently low Curie temperatures of intrinsic 2D ferromagnetic semiconductor materials pose significant limitations on their practical device applications. An effective approach to achieving room-temperature ferromagnetism involves doping non-magnetic semiconductors with specific magnetic atoms. Here, we present the room-temperature ferromagnetism of chromium (Cr)-doped molybdenum disulfide (MoS2) nanosheets synthesized through chemical vapor deposition. The magnetic hysteresis loops, recorded across a temperature span of 10–300 K, underscore the remarkable stability of their magnetic attributes. To gain deeper microscopic insights into the magnetic properties of Cr-doped MoS2, we conducted first-principles calculations, which further validated our experimental findings. This research underscores a promising pathway for the development of 2D ferromagnetic materials with broad application potential in magnetic storage and spin field-effect transistors.

Correction for Mehmood et al., Teacher vaccinations enhance student achievement in Pakistan: The role of role models and theory of mind

Factors influencing secondary school students’ nutrition, mindfulness, and academic performance in Nan Province, Thailand

Academic performance is crucial for future educational endeavors of students. However, there has been a concerning decline over time. This study aimed to investigate the association between nutritional status, environmental factors, mindfulness, and academic performance among students at Bo Kluea School in Nan province, Thailand. A cross-sectional study was conducted involving 350 students in grades 8–11 using questionnaires, measurements, and academic records. Results showed that female students performed significantly better academically compared to males(71.9% vs 56.4% achieving good grades; compared to p &lt; 0.001, OR = 3.583, 95%CI = 1.663–7.719). Age, junk food consumption, BMI, and mindfulness were identified as factors influencing academic performance. Students aged 16–18 years were 2.224 times more likely to achieve good academic performance compared to younger students (p = 0.015, OR = 2.224, 95%CI = 1.164–4.247). Significant associations were found between gender, age, waist circumference, mindfulness, and nutritional status. Female students and those with normal waist circumference or good mindfulness were more likely to have a normal BMI (p = 0.019, OR = 1.794, 95%CI = 1.101–2.922). Positive attitudes towards nutrition were associated with better academic performance (60.1% achieving good grades;p = 0.044, AOR = 1.543, 95%CI = 1.010–2.356). This study highlights the interconnectedness of these factors and their importance in in improving academic results. Further research is need to confirm these findings and overcome study limitations.

A 1 kV sub-nanosecond electrical pulse generated by a linear GaAs photoconductive semiconductor switch and its characterization

The generation of high-voltage ultrafast electrical pulses has significant potential for application in ultrawideband microwave sources, terahertz technology, and inertial confinement fusion. However, there is still a lack of the generation of high-voltage ultrafast electrical pulses with greater peak amplitudes and faster pulse widths and ultrafast characteristics. In this paper, a linear low-temperature gallium arsenide photoconductive semiconductor switch (LT-GaAs PCSS) is developed using the ps-scale carrier lifetime of low-temperature gallium arsenide (LT-GaAs). The generation of ultrafast electrical pulses with a pulse width of 0.5 ns and a voltage amplitude of 1 kV is achieved by triggering a pulsed laser with a wavelength of 1064 nm, a single pulse energy of 70 μJ, and a pulse width of 30 ps. The impact of parameters, such as bias electric field, laser pulse energy, and transmission line length, on the ultrafast characteristics of the output electric pulse of the LT-GaAs PCSS is investigated through a synthesis of experimental and simulation approaches. The results show that (1) in linear conditions, the output pulse amplitude is mainly determined by the bias voltage and laser pulse energy, and the output pulse amplitude is also affected by conductor and dielectric attenuation in the transmission line; (2) the falling edge is determined by the carrier lifetime. Because of the absorption depth at 1064 nm and the carrier lifetime of semi-insulating gallium arsenide material, the output electrical pulse has a trailing edge; (3) the bias voltage and laser pulse energy can improve voltage transmission efficiency, and the saturation of voltage transmission efficiency is caused by the saturation of photon absorption in LT-GaAs material.

Correction for Tran-Kiem and Bedford, Estimating the reproduction number and transmission heterogeneity from the size distribution of clusters of identical pathogen sequences

A twofold perspective on the quality of research publications: The use of ICTs and research activity models

Previous studies have highlighted the inherent subjectivity, complexity, and challenges associated with research quality leading to fragmented findings. We identified determinants of research publication quality in terms of research activities and the use of information and communication technologies by employing an interdisciplinary approach. We conducted web-based surveys among academic scientists and applied machine learning techniques to model behaviors during and after the COVID-19 pandemic. Using model-agnostic explanations, we identified the determinants of research publication quality across 66 activity models. These models reflect the variety of behaviors among academic scientists during and after the COVID-19 pandemic. Our two-fold perspective distinguishes between research activities of academic scientists who increase research publication quality and those who maintain it. Notably, our findings reveal a diversity within activity models in shaping research publication quality. Academic institutions can apply our approach to analyze research staff behavior, stimulate activities, and ensure alignment with institutional objectives, thereby fostering individual and team complementarity.