Substantial Research Interest Research Articles

Pushing the Boundaries of Covalent Organic Frameworks through Postsynthetic Linker Exchange

AbstractCovalent organic frameworks (COFs) are a fast‐developing family of porous organic materials that have received substantial research interest during the last two decades. Dynamic covalent chemistry (DCC) is the cornerstone of COF fabrication. DCC is a process that entails reversible bond breaking‐reforming under equilibrium to attain the thermodynamically most stable structure. Due to the reversible nature of the covalent linkages, the building blocks of pre‐synthesized COF or pre‐assembled chemical entities, like network polymers and supramolecular hosts, can be replaced postsynthetically under appropriate reaction conditions. The technique is known as postsynthetic linker exchange (PLE). PLE provides an easy way to introduce functional building blocks into the COF backbone and control its chemical and physical properties. In this article, we have highlighted the recent advancements (from 2017 to 2023) in the postsynthetic linker exchange strategy for constructing highly crystalline and porous COFs that are often unattainable via de novo fabrication. The mechanistic insights of the linker exchange process for transforming various parent entities, such as COFs, amorphous covalent organic networks, linear polymers, and molecular cages to daughter COFs, have been deliberated with fascinating examples. We have also outlined some future avenues for applying the PLE process for the large‐scale fabrication of highly crystalline COFs for real‐time applications.

Computational Insight into the Nature and Strength of the π-Hole Type Chalcogen∙∙∙Chalcogen Interactions in the XO2∙∙∙CH3YCH3 Complexes (X = S, Se, Te; Y = O, S, Se, Te).

In recent years, the non-covalent interactions between chalcogen centers have aroused substantial research interest because of their potential applications in organocatalysis, materials science, drug design, biological systems, crystal engineering, and molecular recognition. However, studies on π-hole-type chalcogen∙∙∙chalcogen interactions are scarcely reported in the literature. Herein, the π-hole-type intermolecular chalcogen∙∙∙chalcogen interactions in the model complexes formed between XO2 (X = S, Se, Te) and CH3YCH3 (Y = O, S, Se, Te) were systematically studied by using quantum chemical computations. The model complexes are stabilized via one primary X∙∙∙Y chalcogen bond (ChB) and the secondary C-H∙∙∙O hydrogen bonds. The binding energies of the studied complexes are in the range of -21.6~-60.4 kJ/mol. The X∙∙∙Y distances are significantly smaller than the sum of the van der Waals radii of the corresponding two atoms. The X∙∙∙Y ChBs in all the studied complexes except for the SO2∙∙∙CH3OCH3 complex are strong in strength and display a partial covalent character revealed by conducting the quantum theory of atoms in molecules (QTAIM), a non-covalent interaction plot (NCIplot), and natural bond orbital (NBO) analyses. The symmetry-adapted perturbation theory (SAPT) analysis discloses that the X∙∙∙Y ChBs are primarily dominated by the electrostatic component.

From Droplets to Devices: Recent Advances in Liquid Metal Droplet Enabled Electronics

AbstractLiquid metals, particularly non‐toxic gallium‐based alloys, have emerged as promising materials for future soft electronics due to their unique properties, including fluidity, excellent electrical and thermal conductivities, and surface reactivity. They demonstrate adaptability, responsivity, and self‐healing abilities, offering a platform for innovative electronic devices. Embodied in a droplet form factor, gallium‐based liquid metal droplets (LMDs) combine the traits of liquid metals with the advantages of miniaturized structures, including high surface tension, high surface area, high mobility, and surface functionalization. This review discusses the inherent properties of LMDs, which have driven substantial research interest across various fields, such as sensors, robotics, electronic circuits, energy harvesters, drug delivery, and microfluidics systems, among others. Effective fabrication and processing techniques are detailed for LMDs, illustrating their role in applications previously challenging with conventional materials, such as reconfigurable, self‐healing, and transient electronics. Existing challenges and future directions in this growing field are discussed. This extensive review seeks to further the understanding of LMDs and their potential, offering a roadmap for their journey from a niche interest to a key material in various electronic devices.

Monolayer TiC—A high-performance Dirac anode with ultralow diffusion barriers and high energy densities for Li-ion and Na-ion batteries

Two-dimensional Dirac materials have stimulated substantial research interest as binder-free anodes in metal-ion batteries, owing to their ultrahigh electronic conductivity, large specific area, and higher energy density. Here, using first-principles density functional theory calculations, we have investigated the feasibility of monolayer TiC as a potential anode material for Li/Na-ion batteries. The results indicate that monolayer TiC exhibits excellent dynamical and thermal stability. The electronic structure of monolayer TiC shows semimetallic characteristics with a Dirac cone at the M high symmetry point and the formation of Ti or C vacancies transforms the Dirac cone into a nodal loop or a nodal surface, respectively. Thus, monolayer TiC possesses superior electrical conductivity, which can be further enhanced by the formation of Ti or C vacancies in the material. Furthermore, the calculated adsorption energy values of -0.85 and -0.46 eV for Li-ion and Na-ion, respectively, indicate that Li/Na atom adsorption over monolayer TiC is a favorable process. The density of states plots show that after the adsorption of a single Li/Na atom, monolayer TiC maintains its metallic state, which is advantageous for the diffusion of stored electrons. Most remarkably, monolayer TiC exhibits energy densities of 2684 and 2015 mWh/g for Li and Na, respectively, which are significantly higher than commercial graphite and most other 2D anode materials. The fully loaded TiC anode exhibits excellent cycle stability with volume expansions as low as 0.13 and 0.11%, for Li and Na, respectively. Furthermore, an ultrafast diffusivity with low energy barriers of 0.02 and 0.10 eV is found in monolayer TiC for Li-ion and Na-ion, respectively, which suggests that it has an excellent charge/discharge capability. These exceptional properties make monolayer TiC an excellent candidate as an anode material for Li-ion and Na-ion batteries. Finally, SiC(111) has been proposed as a candidate substrate for monolayer TiC due to its minimal lattice mismatch.

Magnetically-dressed CrSBr exciton-polaritons in ultrastrong coupling regime

Over the past few decades, exciton-polaritons have attracted substantial research interest due to their half-light-half-matter bosonic nature. Coupling exciton-polaritons with magnetic orders grants access to rich many-body phenomena, but has been limited by the availability of material systems that exhibit simultaneous exciton resonances and magnetic ordering. Here we report magnetically-dressed microcavity exciton-polaritons in the van der Waals antiferromagnetic (AFM) semiconductor CrSBr coupled to a Tamm plasmon microcavity. Using angle-resolved spectroscopy, we reveal an exceptionally high exciton-photon coupling strength, up to 169 meV, demonstrating ultrastrong coupling that persists up to room temperature. By performing temperature-dependent spectroscopy, we show the magnetic nature of the exciton-polaritons in CrSBr microcavity as the magnetic order changes from AFM to paramagnetic. By applying an out-of-plane magnetic field, we achieve effective tuning of the polariton energy while maintaining the ultrastrong exciton-photon coupling strength. We attribute this to the spin canting process that modulates the interlayer exciton interaction.

Electric Double Layer Effects in Electrocatalysis: Insights from Ab Initio Simulation and Hierarchical Continuum Modeling.

Structures of the electric double layer (EDL) at electrocatalytic interfaces, which are modulated by the material properties, the electrolyte characteristics (e.g., the pH, the types and concentrations of ions), and the electrode potential, play crucial roles in the reaction kinetics. Understanding the EDL effects in electrocatalysis has attracted substantial research interest in recent years. However, the intrinsic relationships between the specific EDL structures and electrocatalytic kinetics remain poorly understood, especially on the atomic scale. In this Perspective, we briefly review the recent advances in deciphering the EDL effects mainly in hydrogen and oxygen electrocatalysis through a multiscale approach, spanning from the atomistic scale simulated by ab initio methods to the macroscale by a hierarchical approach. We highlight the importance of resolving the local reaction environment, especially the local hydrogen bond network, in understanding EDL effects. Finally, some of the remaining challenges are outlined, and an outlook for future developments in these exciting frontiers is provided.

In-plane uniaxial-strain tuning of superconductivity and charge-density wave in CsV3Sb5

The kagome superconductor CsV3Sb5 with exotic electronic properties has attracted substantial research interest, and the interplay between the superconductivity and the charge-density wave is crucial for understanding its unusual electronic ground state. In this work, we performed resistivity and AC magnetic susceptibility measurements on CsV3Sb5 single crystals uniaxially-strained along [100] and [110] directions. We find that the uniaxial-strain tuning effect of T c (dT c/dε) and T CDW (dT CDW/dε) are almost identical along these distinct high-symmetry directions. These findings suggest the in-plane uniaxial-strain-tuning of T c and T CDW in CsV3Sb5 are dominated by associated c-axis strain, whereas the response to purely in-plane strains is likely small.

Two metal-organic frameworks based on tetracarboxylic ligand exhibiting high performance for gas adsorption and separation

Developing porous materials for purification of acetylene is of great significance, but remains challenging. Currently, the use of metal-organic frameworks (MOFs) for gas adsorption separation has received substantial research interest. Herein, based on the tetracarboxylic acid ligand H4TPTA ([1,1':3′,1″-terphenyl]-4,4′,4″,6′-tetracarboxylic acid), two MOFs (ErTPTA and CdTPTA) constructed by trinuclear cluster secondly building units (SBUs) have been successfully synthesized. They are three dimensional (3D) framework with 1D rhomboid channels, demonstrating a (4,8)-connected scu network. A series of gas adsorption tests were performed and the both compounds exhibited outstanding gas selective adsorption performance. Accordingly, the ideal adsorption solution theory (IAST) is used to simulate the adsorption selectivity, the selectivity of CdTPTA for CO2/CH4 is 11.85 (0.5:0.5) and 17.02 (0.05:0.95), and for C2H2/CH4 is 11.81 (0.5:0.5); the selectivity of ErTPTA for C2H2/CO2 is 4.45 (0.5:0.5).

Structural Transformation of Unconventional-Phase Materials.

The structural transformation of materials, which involves the evolution of different structural features, including phase, composition, morphology, etc., under external conditions, represents an important fundamental phenomenon and has drawn substantial research interest. Recently, materials with unconventional phases that are different from their thermodynamically stable ones have been demonstrated to possess distinct properties and compelling functions and can further serve as starting materials for structural transformation studies. The identification and mechanism study of the structural transformation process of unconventional-phase starting materials can not only provide deep insights into their thermodynamic stability in potential applications but also offer effective approaches for the synthesis of other unconventional structures. Here, we briefly summarize the recent research progress on the structural transformation of some typical starting materials with various unconventional phases, including the metastable crystalline phase, amorphous phase, and heterophase, induced by different approaches. The importance of unconventional-phase starting materials in the structural modulation of resultant intermediates and products will be highlighted. The employment of diverse in situ/operando characterization techniques and theoretical simulations in studying the mechanism of the structural transformation process will also be introduced. Finally, we discuss the existing challenges in this emerging research field and provide some future research directions.

Surveying TEFL MA students’ attitude towards research and research methodology course: a mixed research approach

ABSTRACT Research Methodology (RM) is the backbone of any TEFL (Teaching English as a Foreign Language) MA programme. Although a burgeoning body of research has investigated students’ attitude towards research and RM course in various disciplines, students’ attitudes towards research and research methods courses in TEFL research has remained a relatively unexplored area. This mixed-methods study aimed to contribute to this gap in the present research literature. To this end, we administered a 33-item close-ended questionnaire with two open-ended questions to 171 TEFL MA students studying at Iranian universities. IBM SPSS (version 26) was used to analyse quantitative data, and MAXQDA (version 2020) was used to analyse qualitative data. The integrated findings revealed a substantial interest in research and highlighted the right attitude towards RM courses. However, the findings singled out the barriers and impediments EFL students encountered during MA studies. We provide implications for EFL policymakers, EFL departments, and research instructors.

Scientometric review of Web 3.0

Web 3.0 is a next-generation web architecture that envisions a more decentralised, secure and intelligent Internet. Its implications are vast and could potentially impact various research areas, such as e-commerce, social networking, finance, healthcare and education. It can be seen as a confluence of various technological advancements, including blockchain, artificial intelligence, semantic web and decentralised web technologies, which continue to attract substantial research interest in several dimensions and categories throughout the last few decades. A detailed scientometric analysis was undertaken to obtain concise understanding on development and publication trends of this multi-dimensional field. Corpus of 1154 articles, extracted from Web of Science from 2002 to 2022, were used to identify networks of co-authorship, keywords, subject categories, institutions and countries engaged in publishing on Web 3.0 along with co-citation and cluster analysis. Networks and interactive visualisations created using CiteSpace revealed new research areas where Web 3.0 may be beneficial and potential directions of development for Web 3.0 discipline. We identify Journalism 3.0, Personal Data Stores (PDS), Decentralised File Storages (DFS) and Metaverse as emerging domains Web 3.0 research, seeking overwhelming research attention globally.

Methodological and Discursive Considerations for Islamic Bioethics Research and Writing

The past two decades have witnessed a substantial interest in Islamic bioethics research and writing. As more papers are published and a greater number of conferences are held, it is important to reflect on the concepts and concerns that frame the emerging discourse and its nascent academic literature. Accordingly, this paper begins by reflecting on the term Islamic bioethics and the motivations that spur Islamic bioethical deliberation. In so doing, it calls for paying attention to the normative and methodological implications of uniting the disparate discourses represented by the conjunctive term. To further assist consumers in distinguishing various types of Islamic bioethics research and writing, three general categories of scholarly work—Islamic bioethics, Muslim bioethics, and applied Islamic bioethics—are introduced. Next, the paper outlines several lacunae in the extant academic Islamic bioethics literature that emerge from an incomplete engagement with the foundations, elements, and nature of contemporary bioethics discourse. Finally, in order to advance the field and better engage with contemporary bioethical questions, the paper closes by underscoring the need for Islamic bioethics research and writing to become multidisciplinary and involve multilevel ethical analysis.

Mapping 26years of climate change research in finance and accounting: a systematic scientometric analysis.

Climate change and climate finance continue to attract substantial research interest in several dimensions and categories through COVID-19 breakout and resulting disruptions were crucial. An in-depth scientometric analysis was undertaken to gain concise insights on evolution and publication trends of this multi-dimensional field. Corpus of 657 articles, extracted from Web of Science from 1995 to 2020, were used to identify networks of co-authorship, keywords, subject categories, institutions, and countries engaged in publishing on climate finance along with co-citation and cluster analysis. Networks and interactive visualizations created using CiteSpace revealed new research areas where climate finance may be beneficial along with potential directions of development for climate finance discipline. We identify carbon neutrality, accounting for sustainability, planetary boundaries framework, sustainable finance, managing climate risk for third pole, financial innovation and green finance, green swans, COVID pandemic and corporate law and governance in climate finance as emerging domains of climate finance research, seeking overwhelming research attention globally.

Mainstreaming coastally just and equitable marine spatial planning: Planner and stakeholder experiences and perspectives on participation in Latvia

Community participation and influence are vitally important for meeting the multidimensional sustainability aims of marine spatial planning (MSP) and more specifically for procedural and distributive justice. While participation has received substantial research interest, we identify a need to: 1) develop equity-based principles for coastal community participation that can be used to assess and reform MSP practices; 2) generate rich empirical accounts of coastal community participation and representation linked to real-world MSP practices. Here we present the results of a study that synthesizes critical MSP and blue justice scholarship to develop principles and indicators of coastally equitable and just planning. Drawing on interviews with planners and stakeholders and analysis of planning and legal documents, these principles are used to assess participatory processes linked to Latvian MSP practices in the period 2015 to 2019. Our analysis shows that equitable and just MSP needs to be based on participation that is timely, inclusive, supportive & localized, collaborative, methodical and impactful. When applied to the Latvian case these six principles provide a comprehensive and versatile heuristic approach to assess participation in MSP. In the context of Latvian MSP practices, we revealed a fundamental challenge of maintaining inclusive and localized participation throughout the full planning cycle. To counteract the successive narrowing/hardening of participatory space our results indicate a need for continuously promoting diversity of voices and perspectives, opportunities for collaborative sense making, visioning and critique. This will help to bridge diverse MSP divides (e.g., between land and sea, between local, national, and global values and priorities, between science and local knowledge, and between blue growth, conservation, and justice goals). If applied more generally in research and as part of MSP evaluation an equity-based approach can promote the mainstreaming of coastally just and equitable MSP practices. Finally, considering contextual factors (e.g., history, culture, power, legislation) that shape participation and representation is crucial when applying the equity principles to a particular MSP setting to acknowledge and accommodate its particular characteristics and challenges.

Cyclic Peptides with Antifungal Properties Derived from Bacteria, Fungi, Plants, and Synthetic Sources.

Fungal infections remain a significant concern for human health. The emergence of microbial resistance, the improper use of antimicrobial drugs, and the need for fewer toxic antifungal treatments in immunocompromised patients have sparked substantial interest in antifungal research. Cyclic peptides, classified as antifungal peptides, have been in development as potential antifungal agents since 1948. In recent years, there has been growing attention from the scientific community to explore cyclic peptides as a promising strategy for combating antifungal infections caused by pathogenic fungi. The identification of antifungal cyclic peptides from various sources has been possible due to the widespread interest in peptide research in recent decades. It is increasingly important to evaluate narrow- to broad-spectrum antifungal activity and the mode of action of synthetic and natural cyclic peptides for both synthesized and extracted peptides. This short review aims to highlight some of the antifungal cyclic peptides isolated from bacteria, fungi, and plants. This brief review is not intended to present an exhaustive catalog of all known antifungal cyclic peptides but rather seeks to showcase selected cyclic peptides with antifungal properties that have been isolated from bacteria, fungi, plants, and synthetic sources. The addition of commercially available cyclic antifungal peptides serves to corroborate the notion that cyclic peptides can serve as a valuable source for the development of antifungal drugs. Additionally, this review discusses the potential future of utilizing combinations of antifungal peptides from different sources. The review underscores the need for the further exploration of the novel antifungal therapeutic applications of these abundant and diverse cyclic peptides.

Micro-Magnetofluidic System for Rare Cell Analysis: From Principle to Translation

Rare cells play essential roles in the initiation and progression of diseases and therefore their analysis is of great interest. The micro-magnetofluidic system is one of the emerging platforms that have been proposed for the rapid, sensitive, and cost-effective analysis of rare cells. Given its unprecedented throughput, micro-magnetofluidic systems have attracted substantial research interest in the last decade—multiple designs have been proposed, validated, and even advanced to the stage of clinical trials. This mini review aims to provide a timely summary of the relevant progress in the field thus far. We reviewed the concepts and realizations of micro-magnetofluidic devices based on the interaction between nanoparticles and on-chip micro-magnets. Their real-world applications in rare cell analysis were also highlighted and explained. In addition, we discussed the major challenges in the development and translation of micro-magnetofluidic into the clinic, including multi-marker capability and large-scale manufacturability.

Superpixel-guided class-level denoising for unsupervised domain adaptive fundus image segmentation without source data

Unsupervised domain adaptation (UDA), which is used to alleviate the domain shift between the source domain and target domain, has attracted substantial research interest. Previous studies have proposed effective UDA methods which require both labeled source data and unlabeled target data to achieve desirable distribution alignment. However, due to privacy concerns, the vendor side often can only trade the pretrained source model without providing the source data to the targeted client, leading to failed adaptation by classical UDA techniques. To address this issue, in this paper, a novel Superpixel-guided Class-level Denoised self-training framework (SCD) is proposed, aiming at effectively adapting the pretrained source model to the target domain in the absence of source data. Since the source data is unavailable, the model can only be trained on the target domain with the pseudo labels obtained from the pretrained source model. However, due to domain shift, the predictions obtained by the source model on the target domain are noisy. Considering this, we propose three mutual-reinforcing components tailored to our self-training framework: (i) an adaptive class-aware thresholding strategy for more balanced pseudo label generation, (ii) a masked superpixel-guided clustering method for generating multiple content-adaptive and spatial-adaptive feature centroids that enhance the discriminability of final prototypes for effective prototypical label denoising, and (iii) adaptive learning schemes for suspected noisy-labeled and correct-labeled pixels to effectively utilize the valuable information available. Comprehensive experiments on multi-site fundus image segmentation demonstrate the superior performance of our approach and the effectiveness of each component.

A molecular investigation on the mechanism of co-pyrolysis of ammonia and biodiesel surrogates

As renewable energy sources with great potential to reduce carbon footprints and pollutant emissions, ammonia and biodiesel both have garnered substantial research interest. This study aimed to investigate the detailed mechanism of co-pyrolysis of ammonia and biodiesel surrogates, including the pyrolysis of different biodiesel surrogates, the effect of biodiesel decomposition on ammonia reactions, nitric oxide (NO) generation during the ammonia-biodiesel reaction process, and the effect of ammonia on soot formation during biodiesel pyrolysis. Using ReaxFF-based molecular dynamics simulations, the results revealed that the presence of ester groups in biodiesel lowers the activation energy of the reaction compared to alkanes. Meanwhile, biodiesel structures with shorter chain lengths, isomerisation, and carbon-carbon double bond effectively lower the activation energy. Time evolutions of the main pyrolysis products of methyl butanoate (MB), ethyl propionate (EP), and methyl crotonate (MC), as well as their detailed decomposition pathways, were produced. The coexistence of biodiesel and ammonia can promote the decomposition of ammonia, with MC containing carbon-carbon double bonds providing the most abundant free radical environment for ammonia decomposition. High temperature promotes the occurrence of the reaction, with MC, MB, and EP producing NO in the order of MC > MB > EP. Ammonia addition reduces soot production in the pyrolysis of different biodiesel surrogates, with MC exhibiting the most significant effect. The roles of oxygen-containing and nitrogen-containing species in soot suppression and their synergistic impact were identified at the atomic-scale. The insights into the detailed reaction mechanism of the co-pyrolysis of ammonia and biodiesel obtained in this study can be used to guide the development of ammonia-biodiesel co-firing technology.

Decentralized Multi-UAV Cooperative Exploration Using Dynamic Centroid-Based Area Partition

Efficient exploration is a critical issue in swarm UAVs with substantial research interest due to its applications in search and rescue missions. In this study, we propose a cooperative exploration approach that uses multiple unmanned aerial vehicles (UAVs). Our approach allows UAVs to explore separate areas dynamically, resulting in increased efficiency and decreased redundancy. We use a novel dynamic centroid-based method to partition the 3D working area for each UAV, with each UAV generating new targets in its partitioned area only using the onboard computational resource. To ensure the cooperation and exploration of the unknown, we use a next-best-view (NBV) method based on rapidly-exploring random tree (RRT), which generates a tree in the partitioned area until a threshold is reached. We compare this approach with three classical methods using Gazebo simulation, including a Voronoi-based area partition method, a coordination method for reducing scanning repetition between UAVs, and a greedy method that works according to its exploration planner without any interaction. We also conduct practical experiments to verify the effectiveness of our proposed method.

Evaluation of GHK peptide–heparin interactions in multifunctional liposomal covering

Small biospecific peptides with defined chemical structure and cellular responses are promising alternatives to full-length therapeutic proteins. Identification of these peptides solely or in combination with other bioactive factors and determination of their targets are of substantial interest in current drug delivery research. This study is aimed at the development of new liposomal formulations of ECM-derived GHK peptide known for its multiple regeneration-related activities but poorly recognized cellular targets. In situ association of membranotropic GHK derivative with unilamellar liposomes was performed to prepare GHK-modified liposomes with defined properties. According to DLS, the GHK component on the liposomal surface interacted with heparin in a specific manner compared to other polysaccharides and RGD counterpart, whereas ITC analysis of such interactions was complicated. The results provide a useful tool for screening of bio-interactions of synthetic peptide-presenting liposomes by the DLS technique. They were also employed to produce a multi-functional nanosized GHK-heparin covering for liposomes. The resulting composite liposomes possessed low size dispersity, increased anionic charge, and mechanical rigidity. The heparin component significantly promoted the accumulation of GHK-modified liposomes in 3T3 fibroblasts so that the composite liposomes exhibited the highest cell-penetrating activity. Furthermore, the latter formulation stimulated cell proliferation and strongly inhibited ROS production and GSH depletion under oxidative stress conditions. Together, the results support that cell-surface glycosaminoglycans can be involved in GHK-mediated liposomal delivery, which can be further greatly enhanced by association with heparin. The composite liposomes with GHK-heparin covering can be considered as an advanced GHK-based formulation for therapeutic and cosmeceutical applications.