bluuebunny/crossref_metadata_2025 huggingface dataset:
ASMTP: Anonymous secure messaging token‐based protocol assisted data security in swarm of unmanned aerial vehicles
Authors: Manikandan Kayalvizhi , Sriramulu Ramamoorthy
Published: May 2024

Swarm of Unmanned Aerial Vehicles (UAVs) broaden the field of application in various fields like military surveillance, crop monitoring in agriculture, combat operations, etc. Unfortunately, they are becoming increasingly susceptible to security attacks, such as jamming, information leakage and spoofing, as they become more common and in more demand. So, there is a wider need for UAVs, which requires the design of strong security procedures to fend off such attacks and security dangers. Even though several studies focused on security aspects, many questions remain unanswered, particularly in the areas of secure UAV‐to‐UAV communication, support for perfect forward secrecy and non‐repudiation. In a battle situation, it is extremely important to close these gaps. The security requirements for the UAV communication protocol in a military setting were the focus of this study. In this paper, we present the issues faced by the UAV swarm, especially during military surveillance operations. To secure the communication link in UAV, a new protocol for UAV Swarm communication is proposed with anonymous secure messaging token‐based protocol (ASMTP). The proposed protocol secures UAV‐to‐base station communication and safeguards the metadata of the sender and receiver nodes. The proposed model maintains the confidentiality, integrity and availability of data in the UAV Swarm and achieves robustness. In addition, it provides a different strategy for the cybersecurity gaps in the swarm of UAVs during military surveillance and combat operations.
Thermal conductivity of epoxy resin films doped with a polythiophene/graphene complex or aluminum nitride
Authors: Maruyama Tatsuo , Tominaga Yudai , Kado Junko , Morita Kenta , Moriwaki Tomoko , Kusamoto Yoshi , Yoshitomi Tomohiro , Mori Atsunori , Nishino Takashi
Published: May 2024

Polymer composites with thermal conductivity are attractive for heat dissipation in electronic devices. We prepared epoxy resin‐based composite films filled with polythiophene [poly(3‐hexylthiophene‐2,5‐diyl)] (P3HT)/graphene complex or aluminum nitride (AlN). The composite films were characterized by electron microscopic observation, thermogravimetric analysis, and thermal conductivity measurements. The addition of a small content of P3HT/graphene complex (<1 wt%) increased both the out‐of‐plane and in‐plane thermal conductivities of the epoxy resin. The addition of AlN also increased thermal conductivity, but ≥40 wt% was required to obtain thermal conductivity comparable with that of an epoxy resin film doped with 0.9 wt% P3HT/graphene complex. The present results illustrate the potential of P3HT/graphene complexes as fillers for improving the thermal conductivity of epoxy resins without affecting their insulating properties.

Highlights

Polythiophene/graphene fillers increased epoxy resin films' thermal conductivity.

To raise the thermal conductivity of epoxy resin films high AlN content was needed.

In‐plane/out‐of‐plane epoxy resin films' thermal conductivities were evaluated.
Experimental optimization of CuO and MgO hybrid nanoparticle reinforcement ratios to enhance fatigue life of GFRP composites
Authors: Kose Huseyin , Bayar Ismail , Ergün Raşit Koray
Published: May 2024

This study investigated the optimization of CuO and MgO nanoparticle reinforcement ratios within glass fiber‐reinforced polymer (GFRP) composites, and it examined the impact of the hybrid mixture of oxide powders on the mechanical properties of the GFRPs. The study aims to improve the mechanical properties of GFRPs by combining these two powerful nanofillers in various weight ratios to find the best combination to obtain the best fatigue life. Tensile‐tensile fatigue tests were conducted on 25 samples containing hybrid CuO and MgO nanoparticles ranging from 0.0 to 0.8 wt% in 0.2% increments. The test was conducted using a computer‐controlled servo‐hydraulic fatigue device. It was found that the GFRP composite reinforced with hybrid nanoparticles improved the fatigue life. The CuO proportion in the composites partially increased the brittleness properties, while the MgO proportion partially increased the stiffness according to the results. It was found that 0.6 wt% MgO–0.4 wt% CuO and 0.2 wt% MgO–0.6 wt% CuO GFRP composites demonstrated the highest fatigue life yielding at the 39.5k, and 13.7k cycle at 70%, and 80% load level, respectively. The best fatigue life was yielded at the 128k cycle with the 0.4 wt% MgO and 0.6 wt% CuO sample at the 60% load level. According to experimental hysteresis energy loss, 0.4 wt% MgO–0.2 wt% CuO GFRP composite was found to have the highest energy loss. The energy loss increased by approximately 51% in this composite compared to the non‐reinforced composite. The fracture surfaces of a fatigue sample were shown with the SEM image.

Highlights

The GFRP composites were produced by combining MgO and CuO as a hybrid reinforcement.

Analyzed fatigue life using hysteresis curves and S–N graphs.

The fatigue life of GFRP composites was improved with hybrid nanofiller content.

As compared to separate reinforcements with CuO or MgO, the hybrid nanoparticle reinforcement enhanced fatigue life more.
The relationship between teaching experience and teaching outcomes in online teaching during the COVID‐19 pandemic: The mediating role of teaching engagement
Authors: An Tianbo , Wu Peibo , Wang Jingrui , Zhang Huizhen , Chen Zhaojun
Published: May 2024

This study examines the interrelationships of Chinese university teachers' online teaching experiences, online teaching engagement, and online teaching outcomes in the context of the COVID‐19 pandemic. We conducted a survey of 7978 teachers from 235 universities in China from April 2020 to 2021 and explored the relationships among online teaching experiences, teaching engagement, and teaching outcomes in the context of college teachers. The key findings include: (1) Chinese college teachers' online teaching experiences positively predict online teaching engagement, (2) Chinese college teachers' online teaching engagement positively predicts online teaching outcomes, (3) Chinese college teachers' online teaching experiences positively predict online teaching outcomes, and (4) teachers' online teaching engagement partially mediates the relationship between online teaching experiences and online teaching outcomes.
Registration of ‘Independence’ switchgrass
Authors: Lee Moon‐Sub , Casler Michael D. , Lee DoKyoung
Published: May 2024

Switchgrass (Panicum virgatum L.), a valuable forage and bioenergy crop, is established more easily than other native perennial warm‐season grasses, but its establishment is still slower than that of annual crops. Vigorous switchgrass establishment is crucial for achieving its full potential yield and for effectively competing with weeds for water and nutrient availability. To satisfy this demand, ‘Independence’ (Reg. no. CV‐295, PI 704577) switchgrass was developed at the University of Illinois at Urbana‐Champaign. Independence was selected for establishment vigor, winter survivorship, and high biomass yield for two cycles from ‘Kanlow’. It is characterized by rapid establishment, robust seedling growth, and the capacity to achieve peak production by the second year. Independence is well adapted to USDA hardiness zones 5b–7b. In field experiments conducted from 2016 to 2017, averaged over seven locations and all years, Independence annually yielded 13 Mg ha−1 of biomass, outperforming ‘Cave‐in‐Rock’ by 31%, ‘Liberty’ by 15%, ‘Shawnee’ by 42%, ‘Summer’ by 81%, and ‘Sunburst’ by 129%. In wet marginal sites in Illinois from 2020 to 2023, Independence exhibited an average biomass yield of 12 Mg ha−1, outperforming Shawnee by 31%, Liberty by 27%, and Kanlow by 19%, indicating its potential use on less productive land for annual crops. Independence was publicly released by the University of Illinois at Urbana‐Champaign in October 2021.
Interface‐Driven DNA/Metal–Organic Framework Hybrids for Biosensing and Biomedical Applications
Authors: Han Zhaoyu , Li Zhenglian , Liu Biwu
Published: May 2024

Metal–organic frameworks (MOFs) have emerged as promising materials for biosensing and biomedical applications due to their exceptional structural properties and tunable functionalities. Integrating functional DNA with MOFs offers numerous advantages, including enhanced colloidal stability, target‐induced signal amplification, improved cellular uptake, and controlled drug release. This focused review aims to highlight key insights into the DNA–MOF interface to facilitate the design and application of these conjugates. A succinct summary of the interactions between DNA and MOFs, covering both noncovalent adsorption and covalent conjugation is provided. Moreover, recent advancements in utilizing DNA–MOF conjugates in biosensors, with a specific emphasis on fluorescent and electrochemical sensing are discussed. Additionally, applications in bioimaging, controlled drug delivery, and nucleic acid delivery are explored. Finally, the limitations of existing designs and provide insightful perspectives for the future development of DNA–MOFs, aiming to expedite their integration and impact in the realm of biomedical applications are addressed.
Influence of Pressure on Phonon Properties of Indium Antimonide
Authors: Palasyuk Taras , Jastrzebski Cezariusz , Khachapuridze Aleksander , Litwin‐Staszewska Elzbieta , Suski Tadeusz , Grzegory Izabella , Porowski Sylwester
Published: May 2024

Herein, experimental observation of the pressure‐induced softening of the zone‐edge transverse acoustical (TA(X)ze) phonon in the zincblende indium antimonide is for the first time reported. Experimental data allow for determination of Grüneisen parameter for the TA(X)ze phonon mode. The density‐functional theory calculations performed within quasiharmonic approximation at 0 K also reveal the softening of the TA(X)ze at high pressure, although the experimental value of its frequency shift is almost three times smaller than the theoretical one. In contrast, pressure dependences of optical phonons are well reproduced in our calculations. Similar calculations for GaSb and InP result in good agreement with available experimental data for optical and, as opposed to InSb, also for TA(X)ze phonons. The fact that the quasiharmonic theory works well for GaSb and InP may suggest that anharmonicity of acoustical phonons in these compounds is insignificant at room temperature. The possibility of enhanced anharmonicity of TA(X)ze phonon in InSb is discussed. The pressure of transition derived from experimentally determined shift of TA(X)ze frequency for InSb does not fit the recently proposed model of Weinstein working well for over 20 semiconductors, which also shows the specificity of InSb especially in comparison to other cubic III–V semiconductors.
A systematic literature review of research examining the impact of citizenship education on active citizenship outcomes
Authors: Jerome Lee , Hyder Faiza , Hilal Yaqub , Kisby Ben
Published: May 2024

This article reports on a systematic review of the evidence concerning the impact of citizenship education, specifically focusing on the effect of different teaching activities on a range of active citizenship outcomes. It provides a narrative synthesis of 109 articles in peer reviewed journals, representing a wide range of methodological approaches. The review was undertaken for a teacher audience and the research team identified four themes with practical implications. First, we discuss the significance of school ethos and distinguish between distinctive aspects of ethos in the literature including relationships between students and teachers, values and behaviours. Second, we explore some of the characteristics of successful projects, including detailed consideration of the type of projects selected for action by young people, the role of teachers, and the duration of projects. This discussion suggests that, whilst full project cycles (involving students identifying and researching areas for action and devising, implementing and reviewing action plans) are valuable, there is also evidence to suggest that short, partial projects may be easier to implement and still secure comparable benefits. Third, we consider the evidence about whether and how citizenship education can have some compensatory effect, closing the civic gap between different groups of young people. In the fourth theme we consider the wide range of teaching strategies which have been demonstrated to have some success in practice.

Context and implications

Rationale for this study

This literature review was undertaken on behalf of a teacher's organisation to consider the evidence base for citizenship education.

Why the new findings matter

The review demonstrates the breadth of evidence for the positive impact of citizenship education and highlights several avenues for further exploration relating to school ethos, action projects and reducing inequalities.

Implications for researchers and educational institutions

Implications for practice relate to the importance of how students perceive the ethos of the school as a whole, as well as their experiences when learning citizenship. This has specific implications for school leaders whose support is required to nurture a positive school ethos (beyond the formal curriculum). Implications for citizenship teachers include making use of short, partial active citizenship projects more routinely; and adopting strategies for closing the civic gap. Researchers are urged to move beyond large‐scale surveys to explore longitudinal studies in specific contexts to track impacts over time for different students.
Responsive materials nanoarchitectonics at interfaces
Authors: Ariga Katsuhiko
Published: May 2024

Advanced materials could perform functions in response to external stimuli. These are responsive materials. In order for us to develop advanced functional systems with a good responsive nature, we need to create a methodology that goes one step further. It is the artificial architecture of functional material systems based on the knowledge of nanotechnology. The task will be fulfilled by the new concept of nanoarchitectonics. Nanoarchitectonics integrates nanotechnology with various material sciences, basic chemistry, microfabrication techniques, and biological processes to architect functional material systems from atomic, molecular, and nanomaterial units. This review will deal with the nanoarchitectonics of responsive materials related with phenomena at interfaces. In order to demonstrate the effectiveness of responsive materials nanoarchitectonics at interfaces for functional systems of various sizes, this review article is organized by size for various functional systems. Specifically, this review has grouped them into (i) molecular level response, (ii) nanodevice level response, (iii) material level response, and (iv) living cell level response. If the social demand for these materials is fully recognized, such development is expected to efficiently progress. This review article would play a role in stimulating such development.
Building sustainable organizations online: How leaders embed sustainability into organizational culture in virtual contexts
Authors: Lizares Robert Edric Josef R. , Cuyegkeng Maria Assunta C.
Published: May 2024

Business organizations may provide significant contributions toward sustainable development, and their leaders have a critical responsibility in incorporating sustainability into their organizational cultures. However, virtual collaboration creates specific challenges in this task. Although existing literature explores how sustainability is integrated into corporate culture in onsite contexts, a gap exists regarding this process in online teams. As such, this study explores how leaders embed sustainability into organizational culture in virtual contexts. Using thematic analysis on data gathered from interviews with 12 participants, this study suggests that leaders exhibit particular behaviors in this undertaking, including recognizing challenges, engaging employees, role modeling, crafting strategy and planning, monitoring and assessing performance, developing partnerships and activating internal communities, and aligning personal and organizational values. These may be further categorized into intrapersonal, interpersonal and functional leader behaviors, which remain salient in the new normal as organizations balance their virtual and face‐to‐face modes of interaction.
Causal mediation analysis with a three‐dimensional image mediator
Authors: Chen Minghao , Zhou Yingchun
Published: May 2024

Causal mediation analysis is increasingly abundant in biology, psychology, and epidemiology studies and so forth. In particular, with the advent of the big data era, the issue of high‐dimensional mediators is becoming more prevalent. In neuroscience, with the widespread application of magnetic resonance technology in the field of brain imaging, studies on image being a mediator emerged. In this study, a novel causal mediation analysis method with a three‐dimensional image mediator is proposed. We define the average casual effects under the potential outcome framework, explore several sufficient conditions for the valid identification, and develop techniques for estimation and inference. To verify the effectiveness of the proposed method, a series of simulations under various scenarios is performed. Finally, the proposed method is applied to a study on the causal effect of mother's delivery mode on child's IQ development. It is found that cesarean section may have a negative effect on intellectual performance and that this effect is mediated by white matter development. Additional prospective and longitudinal studies may be necessary to validate these emerging findings.
3D Tremella‐Like g‐C3N4/TiO2/HNTs Heterojunction Photocatalyst for Enhanced Photocatalytic Degradation of Rhodamine B From Water
Authors: Di Yuli , Zhang Zhengdong , Jiang Ao , Huang Haiyan , He Xia , Jiao Yu , Wang Cheng
Published: May 2024

Among the traditional treatment processes for purifying wastewater contaminated with Rhodamine B (RhB), semiconductor photocatalysis is the most effective technology because it can oxidize organic pollutants and convert them into CO2, H2O, and other harmless molecules in a safe and efficient manner. According to literature research, it is feasible to enhance the performance of g‐C3 N4 as a photocatalyst by constructing a heterojunction with other photocatalytic materials. Morphological regulation of carbon nitride (g‐C3N4) is a viable strategy for improving its photocatalytic activities. By controlling the morphology of g‐C3N4, factors such as light absorption, specific surface area, charge separation, and reaction sites can be optimized to enhance its photocatalytic efficiency. Three‐dimensional tremella‐like carbon nitride (3DT‐CN) and 3D‐CN/TiO2/HNTs (halloysite nanotubes) were prepared using bubble templates and an impregnation method respectively. The Z‐scheme heterojunction structure constructed by 3D‐CN and TiO2 promotes electron‐hole separation. Catalytic experiments demonstrated that under irradiation for 120 min, the 3D‐CN/TiO2/HNTs catalyst could eliminate 86.48 % of Rhodamine B (RhB). Additionally, active radicals such as e‐, h+, ⋅OH, and ⋅O2‐ are involved in RhB degradation. Therefore, the three‐dimensional tremella‐like 3D‐CN/TiO2/HNTs heterojunction photocatalyst has great potential for environmental purification.
Synthesis of N‐Acyl Indole‐3‐Carboxaldehyde Derivatives and Polyvinyl Alcohol Acetalization with 1‐Propionylindole‐3‐Carboxaldehyde
Authors: Perwin Aashna , Mazumdar Nasreen
Published: May 2024

A series of seven stable amide derivatives based on indole‐3‐carboxaldehyde were synthesized with high yields using various aliphatic and aromatic acyl chlorides, triethylamine and DMAP as the catalyst at room temperature. Structural characterization was performed using FT‐IR, 1 H‐NMR, 13C‐NMR and LC–MS techniques. To develop bioactive material, acetalization of water‐soluble polyvinyl alcohol was achieved by reacting one of the N‐acyl derivatives, 1‐propionylindole‐3‐carboxaldehyde, in the presence of a p‐TSA catalyst to form polyvinyl acetal with pendant bioactive groups. The polymer was analyzed using 1 H‐NMR, FT‐IR, TGA, DSC, FE‐SEM and EDX spectroscopic techniques. The polymer was water‐insoluble with enhanced thermal stability compared to pure polyvinyl alcohol. This approach for developing N‐acyl derivatives of indole‐3‐carboxaldehyde and then reacting one of the monomers with polyvinyl alcohol to improve its thermal properties and stability in humid conditions has proven successful.
Sustainable Sol‐Gel Approach for Visible Light‐Responsive Titanium Dioxide Nanoparticles in Efficient Diazinon Removal
Authors: Mohamad Idris Nurul Hidayah , Abdul Mu'minin Aina Hanin , Yoon Tiem Leong , Ohno Teruhisa , Lee Hooi Ling
Published: May 2024

This study addresses water pollution challenges by employing photocatalysis as an effective solution. Titanium dioxide (TiO2) with unique characteristics is widely utilized in this approach. However, the design of nanosized TiO2 particles is crucial for enhancing photocatalytic performance during diazinon's photodegradation. As such, the TiO2 nanoparticles (NPs) were synthesized via the green sol‐gel method in this study, exhibit a mixed anatase‐brookite phase, a small particle size of 11.17 nm, and lower bandgap energy (3.00 eV) than pure anatase TiO2 of 3.20 eV, rendering them active under visible light. DFTB calculation was deployed to investigate the role of oxygen vacancies in reducing the bandgap energy. Experimentally measured (3.00 eV) and computationally (2.812 eV) determined bandgap energies align well. The TiO2 NPs demonstrate significant photocatalytic efficacy, degrading 73.3 % of diazinon within 210 min under sunlight, with a mineralization degree of 43.50 %, and 2‐isopropyl‐6‐methylpyrimidin‐4‐ol (IMP) was detected as the intermediate product. The photodegradation follows first‐order kinetics, and adsorption isotherm analysis fits the Langmuir model. ⋅O2− is identified as the predominant reactive oxygen species in the diazinon's photodegradation. Hence, the synthesized TiO2 NPs offer good reusability, maintaining a degradation efficiency of 67.4 % even after five cycles, showing good potential for wastewater treatment applications.
Judd–Ofelt Intensity Parameters and Optical Properties of Eu/Li Co‐Doped CeO2 Phosphor
Authors: Hai Nguyen Van , Van Hoang Nhu
Published: May 2024

In this work, the intense orange‐red emission of Eu3+ singly and Eu3+/Li+ co‐doped CeO2 phosphors synthesized by solution combustion using urea as fuel was investigated experimentally and theoretycally. X‐ray diffraction and high‐resolution transmission electron microscope analysis confirmed the formation of a single‐phase CeO2 cubic with high crystallinity. Under 360 nm excitation, the phosphors emitted an intense orange–red region of Eu3+ as a function of Li+ doping content. Significantly, it was enhanced 12/10 times by Li+ co‐doping due to the increased crystallinity of the host lattice. The energy transfer proccesse associated with cross‐relaxation is responsible for decreasing the experimental lifetime of Eu3+. The influence of Li+ doping content on the characterization properties of CeO2:Eu, Li phosphors was further explained using Judd‐Ofelt (J−O) theory, from which branching ratios (βr), transition probability (A), radiative lifetime (τcal), and stimulated cross‐section (σe) emission of the phosphors were estimated. The results indicate that an effectively improved crystallinity by Li+ co‐doped CeO2:Eu can significantly enhance its luminescence intensity, making it suitable for optoelectronic and display applications.
Setting the tone to get their way: An attention‐based approach to how narcissistic CEOs influence the board of directors to take more risk
Authors: Tuggle Christopher S. , Borgholthaus Cameron J. , Harms Peter D. , O'Brien Jonathan P.
Published: May 2024

Research Summary

Upper echelons research has generated insights into the organizational consequences of CEO narcissism. However, fewer studies have empirically attended to the mechanisms through which these consequences occur. Using the attention‐based view, we introduce a process model examining how CEO narcissism is linked to corporate risk‐taking through the board of director discussion tone of risk‐taking during board meetings. We further note that narcissistic CEOs have an increased ability to do so when they are appointed to be board chair. We find strong support for each of our hypotheses by utilizing a unique data set of corporate board meeting transcripts encompassing 88 public firms and 197 CEOs over 20 years. Our results suggest that narcissistic CEOs are adept at controlling the attentional foci of boards of directors to get their way.

Managerial Summary

Our study offers an explanation as to how CEO narcissism influences firm risk‐taking behavior. Specifically, we demonstrate that narcissistic CEOs are prone to drive board discussions about risk‐taking to hold a positive tone—especially when they also serve as board chair—thereby enabling them to allocate increased resources toward risk‐taking strategies. Through an extensive analysis of board meeting transcripts spanning two decades across 88 companies, we illustrate how narcissistic CEOs wield substantial influence in molding board conversations to mirror their own pro‐risk inclinations. This insight further considers the importance of understanding CEO behavior in guiding risk management strategies in the future.
Vacancy‐Defect Ternary Topological Insulators Bi2Se2Te Encapsulated in Mesoporous Carbon Spheres for High Performance Sodium Ion Batteries and Hybrid Capacitors
Authors: Hu Lijuan , Liu Changyu , Zhang Fan , Wang Hui , Wang Beibei
Published: May 2024

Ternary topological insulators have attracted worldwide attention because of their broad application prospects in fields such as magnetism, optics, electronics, and quantum computing. However, their potential and electrochemical mechanisms in sodium ion batteries (SIBs) and hybrid capacitors (SIHCs) have not been fully studied. Herein, a composite material comprising vacancy‐defects ternary topological insulator Bi2Se2Te encapsulated in mesoporous carbon spheres (Bi2Se2Te@C) is designed. Bi2Se2Te with ample vacancy‐defects has a wide interlayer spacing to enable frequent insertion/extraction of Na+ and boost reaction kinetics within the electrode. Meanwhile, the Bi2Se2Te@C with optimized yolk–shell structure can buffer the volume variation without breaking the outer protective carbon shell, ensuring structural stability and integrity. As expected, the Bi2Se2Te@C electrode delivers high reversible capacity and excellent rate capability in half SIB cells. Various electrochemical analyses and theoretical calculations manifest that Bi2Se2Te@C anode confirms the synergistic effect of ternary chalcogenide systems and suitable void space yolk‐shell structure. Consequently, the full cells of SIB and SIHC coupled with Bi2Se2Te@C anode exhibit good performance and high energy/power density, indicating its widespread practical applications. This design is expected to offer a reliable strategy for further exploring advanced topological insulators in Na+‐based storage systems.
Elucidating Structural Disorder in Ultra‐Thin Bi‐Rich Bismuth Oxyhalide Photocatalysts
Authors: Marks Melissa , Jeppesen Henrik , Nielsen Mads Lund Nygaard , Kong Jintao , Ceccato Marcel , van der Veen Monique A. , Bøjesen Espen Drath , Lock Nina
Published: May 2024

Advancing the field of photocatalysis requires the elucidation of structural properties that underpin the photocatalytic properties of promising materials. The focus of the present study is layered, Bi‐rich bismuth oxyhalides, which are widely studied for photocatalytic applications yet poorly structurally understood, due to high levels of disorder, nano‐sized domains, and the large number of structurally similar compounds. By connecting insights from multiple scattering techniques, utilizing electron‐, X‐ray‐ and neutron probes, the crystal phase of the synthesized materials is allocated as layered Bi24O31X10 (X = Cl, Br), albeit with significant deviation from the reported 3D crystalline model. The materials comprise anisotropic platelet‐shaped crystalline domains, exhibiting significant in‐plane ordering in two dimensions but disorder and an ultra‐thin morphology in the layer stacking direction. Increased synthesis pH tailored larger, more ordered crystalline domains, leading to longer excited state lifetimes determined via femtosecond transient absorption spectroscopy (fs‐TAS). Although this likely contributes to improved photocatalytic properties, assessed via the photooxidation of benzylamine, increasing the overall surface area facilitated the most significant improvement in photocatalytic performance. This study, therefore, enabled both phase allocation and a nuanced discussion of the structure‐property relationship for complicated, ultra‐thin photocatalysts.
Application of Intercritical Austenitizing in a Commercial CMnSi Steel as a Tool for Optimizing a One‐Step Quenching and Partitioning Cycle Aiming to Achieve a Third‐Generation Advanced High‐Strength Steel
Authors: Magalhães Charles H. X. M. , Corrêa Elaine C. S. , Faria Geraldo L.
Published: May 2024

Advanced high‐strength steels (AHSS) have been extensively studied to develop its third generation from relatively low‐cost alloys, but seeking optimized mechanical properties. In this context, the effects of quenching heat treatments are evaluated in this work after intercritical austenitizing (IA) on microstructure, alloying elements partitioning, and Ms temperature for a commercial CMnSi alloy. Applying dilatometric data and microstructural characterization, different heat cycles are evaluated. The obtained experimental results are compared with those ones obtained by computer simulations at equilibrium conditions. Based on this characterization, an optimized one‐step quenching and partitioning (Q&P) cycle (after IA) is proposed and applied to tensile test specimens. Then, the specimen microstructure is characterized by scanning and transmission electron microscopy as well as by X‐ray diffraction. Using the proposed methodology, it is possible to produce a Q&P steel with a product of tensile strength and elongation of 29.5 GPa% and a 7% volumetric fraction of retained austenite. It is concluded that the precise knowledge about the IA effects on the phase transformations and microstructure evolution in a commercial CMnSi alloy has great potential to be applied in defining a one‐step Q&P heat treatment that favors a multiphase microstructure, which meets mechanical properties requirements for a third‐generation AHSS.
Inclusions Evolution of Ca‐Treated Steel During High‐Heat Input Welding
Authors: Qi Huan , Pang Qihang , Li Weijuan , Bian Shouyuan
Published: May 2024

This article has investigated a 60 mm Ca‐treated Q550 steel used for high‐heat input welding. The results have shown that the Ca‐type inclusions account for 70% of the inclusions in the steel which are mainly CaAlMg type, Ca–Al type, and a small amount of CaS type while the non‐Ca‐type inclusions are mainly FeCO. After undergoing the welding thermal cycle, the number of Ca‐containing inclusions above 2 μm in size is decreased while the number of non‐Ca‐containing inclusions below 1 μm (mainly FeO) is increased significantly. However, the total area of inclusions is decreased. It has been found out that the CaAlSO‐type inclusions undergo “diffusion” of O element to the surroundings during the thermal cycle, forming a ring‐shaped oxygen‐rich zone and carbon‐rich zone which promotes the nucleation of acicular ferrite. In contrast, the CaAlMgSO‐type inclusions undergo “decomposition” during the thermal cycle which forms a group of inclusions with different sizes and types, promoting nucleation of multioriented acicular ferrite.
Traglastversuche an Großprüfkörpern für modulare Polygonturmsektionen von Windenergieanlagen
Authors: Keindorf Christian , Bülow Tim , Kaschner Hartmut
Published: May 2024

Bei der Bemessung von Stahltürmen für Onshore‐Windenergieanlagen führen oftmals Stabilitäts‐ und Ermüdungsnachweise infolge der hohen statischen und dynamischen Beanspruchungen zu großen Turmabmessungen. Aufgrund der Steigerung von Nennleistung und Nabenhöhe für Windturbinen müssen auch die Dimensionen bei den Tragstrukturen erhöht werden. Einige Anlagentypen erfordern mittlerweile einen Turmfußdurchmesser von > 4,5 m. In diesen Durchmessern lassen sich Turmsektionen auf der Straße nicht mehr (wirtschaftlich) transportieren. Daher sind vermehrt modulare Bauweisen entwickelt worden, wobei die Stahlsektionen aus längsgeteilten Segmenten bestehen, die auf der Baustelle endmontiert werden. Des Weiteren stellt die Verbindungstechnik für turmartige Bauwerke immer wieder eine neue Herausforderung dar, wenn größere Windenergieanlagen geplant werden. Als technische Alternative zu den bisherigen Turmkonfigurationen wird ein Konzept für einen modularen Polygonturm vorgestellt, dessen Plattensegmente entlang der Längskanten über Strangpressprofile verbunden werden sollen, sodass am Standort keine weiteren Schraub‐ oder Schweißverbindungen erforderlich sind. Durch diese innovative Verbindungstechnik und die längsorientierte Fertigung von ebenen Turmsegmenten sollen Umformprozesse und teilweise auch Schweißprozesse während der Fertigungsphase eingespart werden, die bislang bei den rohrförmigen Stahltürmen erforderlich sind. Im Rahmen eines Forschungsprojekts wurde die technische Machbarkeit eines modularen Polygonturms für eine Anlagenklasse mit 10 MW Nennleistung und 200 m Nabenhöhe analysiert, um Lösungsansätze für die nächste Generation von Onshore‐Windenergieanlagen anbieten zu können. Für eine fiktive Referenz‐Windenergieanlage wurden Lastfälle generiert, um Bemessungen für die Turmsektionen durchführen zu können. Auf Basis der berechneten Turmabmessungen wurde ein Versuchsprogramm erstellt und es wurden Traglastversuche an Großprüfkörpern im Maßstab 1 : 10 durchgeführt. In diesem Aufsatz werden die Ergebnisse der experimentellen Untersuchungen vorgestellt, wobei die Traglasten der einzelnen Turmkonfigurationen miteinander verglichen und die Versagensmechanismen erläutert werden.
Enacting a Global Englishes and Critical Pedagogy Integrated Curriculum in Korean High School English as a Foreign Language Classrooms
Authors: Jung Hyeyoung , Crookes Graham V.
Published: May 2024

This study examines the enactment of Global Englishes (GE) curriculum in public high school English as a foreign language classrooms in South Korea. Data collection involved pre‐ and post‐course surveys (N = 217, nine classrooms), students' written responses, and their oral presentations. The findings highlight the necessity of adopting a critical perspective as the initial step to incorporate GE in these classrooms. They also recommend integrating GE curriculum within the existing assessment framework. After curriculum enactment based on critical pedagogy and GE took place over the course of a year, the results from the post‐course survey indicated positive changes in students' receptiveness to GE, their perceptions of Outer Circle varieties, and their confidence in engaging in intercultural communication. Students' written responses also demonstrated an enhanced critical awareness of GE‐related issues. However, there was no significant change in their perceptions regarding the exclusion of GE in listening tests, their low preference for Expanding Circle varieties, and their limited multicultural communication skills. The pedagogical implications of this study are relevant not only for GE educators but also for those who enact locally driven curriculum innovations within test‐oriented contexts.
Sustainability‐driven optimization of microwave‐assisted extraction for enhanced corilagin and total phenolic compound yield from Dimocarpus longan
Authors: Fuangchoom Varunya , Narkprasom Nukrob , Jaturonglumlert Somkiat , Varith Jaturapatr , Unpaprom Yuwalee , Narkprasom Kanjana
Published: May 2024

The longan fruit, widely grown and consumed in Southeast Asia, contains an abundance of essential natural chemicals present in its flesh and seeds. The microwave‐assisted approach is used to extract these components, which include total phenolic compound and corilagin. The optimization of the extraction process included factors such as the sample ratio (0.5–1.5 g/30 mL), time (10–20 min), and microwave power (600–700 W). These variables were examined using the response surface approach. The statistical analysis revealed that the data was most accurately represented by a quadratic polynomial equation. The decision coefficients for total phenolic compounds and corilagin were found to be 0.9956 and 0.9485, respectively, indicating a high level of accuracy. The result was that the optimal conditions to obtain the highest total phenolic compound and corilagin from longan extract are 22.214 mgGAE/gDW and 55.137 mg/gDW, respectively. The sample was extracted under a ratio of 0.97 g/30 mL set at microwave power at 695.74 W, with an extraction time of 15 min. This study suggests that microwave‐assisted, water‐based extraction can produce healthful, eco‐friendly concentrated longan extracts, yielding high levels of corilagin and phenolic compounds.
Impact of Bisphenol‐A in the environment and its removal through biological agents: A review
Authors: Gupta Akanksha , Singh Anubhuti , Mishra Virendra Kumar
Published: May 2024

Endocrine‐disrupting chemicals (EDCs) are synthetic compounds that can cause abnormalities in the functioning of the endocrine system of the human being, resulting in various health problems. Bisphenol‐A (BPA) is one of the important EDCs that is used in the manufacturing of plastics, food packaging canisters, and other day‐to‐day necessities. Since BPA is estrogenic in nature; its presence can affect the living component at a very low concentration. BPA and other EDCs are released from various sources like the plastic manufacturing industry, sewage treatment plants, and solid waste disposal points. Due to its global use, BPA has permeated different matrices, including our food sources. As a result, many adverse health effects have been reported, considering which, their treatment is necessary. Under the present investigation, we have reviewed various studies dealing with the sources, concentrations, and impact of BPA on the environment. In addition, we have also incorporated different treatment technologies including phytoremediation and bioremediation which can remove BPA effectively. Regardless of significant developments in our understanding of EDCs, uncertainties and knowledge gaps still occur and more studies are required to eradicate the problems of BPA contamination from our environment.
Dominant stricture in paediatric‐onset primary sclerosing cholangitis is associated with impaired prognosis in a long‐term follow‐up
Authors: Tenca Andrea , Kolho Kaija‐Leena , Consonni Dario , Jokelainen Kalle , Färkkilä Martti
Published: May 2024

Background and Objectives

The impact of dominant stricture (DS) on the outcomes of paediatric‐onset primary sclerosing cholangitis (PSC) is unknown. This study was aimed at investigating the impact of DS on the clinical course and prognosis of patients with paediatric‐onset PSC.

Methods

Patients with paediatric‐onset PSC diagnosed between January 1993 and May 2017 were identified from hospital records or our PSC registry. Data including clinical, laboratory, cholangiography, and cytology at diagnosis and during follow‐up (until July 2023) were reviewed. We graphed the Kaplan‐Meier failure function and fitted crude and multivariable Cox model to calculate hazard ratios (HR) and 95% confidence intervals (CI) for selected variables. In these analyses, DS was treated as a time‐varying variable.

Results

We identified 68 patients (42 males) with paediatric‐onset PSC (median age at diagnosis 15 years). The median follow‐up was 13 years and the median age at the last follow‐up was 27 years. In total, 35 (51%) had concomitant autoimmune hepatitis. DS was diagnosed in 33 patients (48%): in eight at the time of PSC diagnosis (12%) and in 25 (37%) by the end of follow‐up. In patients with DS, two developed cirrhosis, seven were transplanted and one patient was operated for a biliary mass with low‐grade dysplasia. In patients without a DS, two developed cirrhosis, and four were transplanted; one female was excluded from survival analysis because she already had cirrhosis at the time of PSC diagnosis. Cirrhosis or biliary dysplasia or needing liver transplantation for these indications were more frequent after the development of DS (10/33, adjusted HR 4.26, 95%CI: 1.26–14.4). No cholangiocarcinomas or deaths occurred during the follow‐up.

Conclusions

DS was present at diagnosis or developed during follow‐up in about half of the patients with paediatric‐onset PSC and was associated with impaired outcome.
The use of C‐reactive protein to predict uncomplicated appendicitis and increase uptake of laparoscopy in low resource hospitals—A retrospective cohort study
Authors: Brombacher Michael , Moolla Haroon , Nair Vimal , Clarke Damian
Published: May 2024

Background

Acute appendicitis remains the most common surgical emergency worldwide. There has been a low uptake of laparoscopic appendicectomy in the South African public sector. Preoperative identification of cases of uncomplicated appendicitis that are amenable to a laparoscopic approach may facilitate the implementation of laparoscopic appendicectomy programs in training hospitals. With limited access to preoperative imaging, alternative strategies for this preoperative prediction are needed.

Methods

A retrospective audit of patients over the age of 12 years with a histologically confirmed diagnosis of acute appendicitis over a 5‐year period was performed. Patients were categorized as uncomplicated or complicated appendicitis and C‐reactive protein (CRP) and white cell count (WCC) reviewed. Receiver operating characteristics curves were constructed for these blood tests and acute appendicitis severity. Youden's J statistic was used to determine optimal cut off values for diagnosing complicated appendicitis.

Results

358 patients had confirmed appendicitis and complete blood results. Of these, 189 (52.79%) had complicated appendicitis with a 40.22% perforation rate. Median CRP in uncomplicated and complicated groups were 68 mg/L (IQR 19–142) and 216 mg/L (IQR 103–313) with an area under the curve (AUC) of 0.75 (95% CI: 0.70–0.80). The median WCC in the two groups were 12.6 × 109 cells/L (IQR 9.9–15.6) and 14.4 × 109 cells/L (IQR 11.5–18.28) with an AUC of 0.61 (95% CI: 0.56–0.67). The optimal cut off value for CRP was found to be 110 mg/L with a sensitivity of 74.74% and specificity of 69.23%.

Conclusion

A cutoff value of 110 mg/dl CRP can distinguish patients with early appendicitis from those with complicated disease and when used in conjunction with clinical assessment may help identify patients in whom laparoscopic appendicectomy is appropriate.
Recent Advances in Machine Learning Assisted Hydrogel Flexible Sensing
Authors: Zhou Song , Song Dengke , Pu Lisha , Xu Wenlong
Published: May 2024

Hydrogel flexible sensors are widely used in wearable devices, health care, intelligent robots and other fields due to their excellent flexibility, biocompatibility and high sensitivity. With the development of single sensor to multi‐channel and multi‐mode sensor network, the sensor data also presents the characteristics of multi‐dimension, complex and massive. Traditional data analysis methods can no longer meet the data analysis requirements of hydrogel flexible sensor networks. The introduction of machine learning (ML) technology optimizes the process of data analysis. With the continuous development of multi‐layer neural network technology and the improvement of computer performance, deep learning (DL) algorithm is increasingly used to achieve higher efficiency and accuracy, provides a powerful tool for data analysis of hydrogel flexible sensor, and accelerates the intelligent process of hydrogel flexible sensor equipment. This paper introduces the classification of hydrogel flexible sensors and the working mechanism and common algorithms of ML, and summarizes the application of ML technology to assist hydrogel flexible sensors in data analysis in the fields of health care and information recognition. This review will provide inspiration and reference for integrating ML technology into the field of hydrogel flexible sensors.
Species scale in diverse dimensions
Authors: van de Heisteeg Damian , Vafa Cumrun , Wiesner Max , Wu David H.
Published: May 2024

Abstract

In a quantum theory of gravity, the species scale Λs can be defined as the scale at which corrections to the Einstein action become important or alternatively as codifying the “number of light degrees of freedom”, due to the fact that $$ {\Lambda}_s^{-1} $$

Λ
s

−
1

is the smallest size black hole described by the EFT involving only the Einstein term. In this paper, we check the validity of this picture in diverse dimensions and with different amounts of supersymmetry and verify the expected behavior of the species scale at the boundary of moduli space. This also leads to the evaluation of the species scale in the interior of the moduli space as well as to the computation of the diameter of the moduli space. We also find evidence that the species scale satisfies the bound $$ {\frac{\left|\nabla {\Lambda}_s\right|}{\Lambda_s}}^2\le \frac{1}{d-2} $$

∇

Λ
s

Λ
s

2

≤

1

d
−
2

all over moduli space including the interior.
The classical double copy in curved spacetimes: perturbative Yang-Mills from the bi-adjoint scalar
Authors: Prabhu Siddharth G.
Published: May 2024

Abstract

We formulate a version of the double copy for classical fields in curved spacetimes. We provide a correspondence between perturbative solutions to the bi-adjoint scalar equations and those of the Yang-Mills equations in position space. At the linear level, we show that there exists a map between these solutions for maximally symmetric spacetime backgrounds, that provides every Yang-Mills solution by the action of an appropriate differential operator on a bi-adjoint scalar solution. Given the existence of a linearized map, we show that it is possible to cast the solutions of the Yang-Mills equations at arbitrary perturbation order in terms of the corresponding bi-adjoint scalar solutions. This all-order map is reminiscent of the flat space BCJ double copy, and works for any curved spacetime where the perturbative expansion holds. We show that these results have the right flat space limit, and that the correspondence is agnostic to the choice of gauge.
Binary AdS black holes coupled to a bath in Type IIB
Authors: Deddo Evan , Zayas Leopoldo A.Pando , Uhlemann Christoph F.
Published: May 2024

Abstract

We construct Type IIB string theory setups which, via double holography, realize two gravitational systems in separate AdS spaces which interact with each other and with a non-gravitational bath. We employ top-down string theory solutions with concrete field theory duals in the form of 4d $$\mathcal{N}$$ = 4 SYM BCFTs and a first-principles notion of double holography. The setups are used to realize pairs of ‘near’ and ‘far’ black holes from the perspective of the bath, which exchange Hawking radiation with each other and radiate into the bath. We identify three phases for the entropy in the bath characterized as no island, partial island and full island, and discuss the entropy curves. The setups differ from the black hole binaries observed in gravitational wave experiments but may capture certain aspects.