Dynamic Exchange Research Articles

A Blockchain-Integrated Federated Learning Approach for Secure Data Sharing and Privacy Protection in Multi-Device Communication

ABSTRACT The secure transmission of communication data between different devices still faces numerous potential challenges, such as data tampering, data integrity, network attacks, and the risks of information leakage or forgery. This approach aims to handle the distributed trust issues of federated learning users and update data states rapidly. By modeling multi-source devices through federated learning, the model parameters and reputation values of participating devices are stored on the blockchain. This method incorporates factors such as experience, familiarity, and timeliness to more quickly gather reliable information about nodes to assess their behavior. Simulation results on the MNIST dataset show that when the proportion of selfish nodes is below 50%, the convergence time increases with the proportion of selfish nodes. Compared to advanced algorithms, the proposed model saves approximately 6% of interaction time. As the number of transactions significantly increases, the system’s TPS (Transactions Per Second) decreases, with an average TPS of only 3079.35 when the maximum number of transactions is 4000. The proposed scheme can filter out high-quality data sources during real-time dynamic data exchange, enhancing the accuracy of federated learning training and ensuring privacy security.

Rapid and Versatile Functionalization of Poly-Ethylene Imine via Dynamic Aminal Formation.

The study of dynamic covalent chemistry (DCC) is growing rapidly in polymer chemistry. The dynamic covalent chemistry of polyaminals formed by the reaction of linear polyethyleneimine (L-PEI) with various functional aldehydes is explored. The study demonstrates the pH-dependent kinetics of polyaminal formation and the versatility of polyaminals in controlling the release of aldehydes under ambient conditions. Additionally, the controlled temperature-induced release of aldehydes and the dynamic shuffling behavior of aminals in polymer systems are investigated, emphasizing the potential for dynamic, covalently bonded polymers through dynamic aminal chemistry. The research showed the dynamic covalent aminal exchange for creating a range of new polymer materials.

Sodium aluminosilicate synthesised from rice straw as a sorption barrier to protect soil from antimony contamination

ABSTRACT A novel effective sorbent for the extraction of antimony(III) from rice straw has been generated, having a specific surface area of 470 m²/g. The material was subjected to a series of analyses, including scanning electron microscopy, energy dispersive X-ray analysis, X-ray diffraction analysis, and FT-IR spectroscopy. The sorption properties relative to Sb(III) ions were characterised in dynamic conditions in a column experiment. The total dynamic exchange sorption capacity of 113.92 mg/g renders this material suitable for use as a permeable reactive barrier (sorption barrier) with the objective of protecting soils from antimony contamination. To identify the optimal conditions for soil protection, the chemical composition, acid-base properties, and sorption parameters of soils of varying types were characterised. The sorption properties of the soils were determined in static conditions to obtain the sorption isotherm. The maximal sorption capacity was identified for the soil sample with low base saturation and a high organic component content, a finding that was corroborated by DTA analysis. The results of the column experiment with layers of soil and aluminosilicate sorbent indicate the promising use of the new sorbent as a sorption barrier for the effective protection of soils from antimony contamination.

한국 H 서예 동아리에서의 문화 간 교류와 문화 적응 : 중국 유학생의 관찰과 체험

This study uses ethnography to explore the cross-cultural exchange experiences of a Chinese student in the Korean H Calligraphy Club, emphasizing the unique role of calligraphy in cross-cultural interaction. Researcher A, with a background in Chinese calligraphy, came to Korea for advanced studies in applied art education. Through active participation in the H Calligraphy Club, he experienced cultural shock and gradually adapted to the new environment. The study’s findings are organized into three themes: Cultural Shock and Decapsulation, Localization of Calligraphy, and Conscious and Unconscious Cross-Cultural Interaction. Initially, Researcher A saw Korean Chinese-character calligraphy as an extension of Chinese calligraphy. However, through interviews and observations, he recognized the originality and localization of Korean calligraphy and its role in cultural exchange. This study reveals how the H Calligraphy Club serves as a platform for cultural interaction, highlighting the dynamics of contemporary cultural exchange and providing insights for future cross-cultural research.

Seasonal patterns of CO2 exchange in a tropical intensively managed pasture in Southeastern Brazil

Tropical pastures are one of the main land uses in Brazil, forming the backbone of the country's beef and milk production chain. Adopting sustainable management practices that increase the productivity of pastoral livestock systems is essential to mitigate environmental impacts and ensure food security. However, eddy covariance studies that contribute to understanding the influence of grazing management strategies on the ability of intensively grazed tropical pastures to absorb carbon remain scarce. Therefore, our main objective was to investigate the dynamics of CO2 and water vapor exchange and biomass production in a tropical C4 grass (Pennisetum purpureum Schum. cv. Cameroon) pasture under intermittent stocking management strategies from March 2021 to June 2023. We found that the pasture acted as a net source of CO2 to the atmosphere in both years studied. The annual NEE was 34 ± 14 g CO2-C m−2 yr−1 in 2021–2022 and 21 ± 12 g CO2-C m−2 yr−1 in 2022–2023. Reco, influenced by rising air and soil temperatures, increased rainfall, and higher incoming solar radiation levels, especially during spring and summer, played a crucial role in this result. The pasture absorbed more CO2, showed higher evapotranspiration, and produced more leaves in the rainy periods when the pasture structure was kept close to the previously established management targets. CO2 losses to the atmosphere prevailed in the dry periods and in wet periods where the pasture structure was far from the optimal limits for elephant grass.

Dynamic fibrillar assembly of αB-crystallin induced by perturbation of the conserved NT-IXI motif resolved by cryo-EM

αB-crystallin is an archetypical member of the small heat shock proteins (sHSPs) vital for cellular proteostasis and mitigating protein misfolding diseases. Gaining insights into the principles defining their molecular organization and chaperone function have been hindered by intrinsic dynamic properties and limited high-resolution structural analysis. To disentangle the mechanistic underpinnings of these dynamical properties, we ablate a conserved IXI-motif located within the N-terminal (NT) domain of human αB-crystallin implicated in subunit exchange dynamics and client sequestration. This results in a profound structural transformation, from highly polydispersed caged-like native assemblies into an elongated fibril state amenable to high-resolution cryo-EM analysis. The reversible nature of this variant facilitates interrogation of functional effects due to perturbation of the NT-IXI motif in both the native-like oligomer and fibril states. Together, our investigations unveil several features thought to be key mechanistic attributes to sHSPs and point to a critical significance of the NT-IXI motif in αB-crystallin assembly, polydispersity, and chaperone activity.

The dynamics of exchange traded funds: a geometrical and topological approach

Using a metric related to the returns correlation, a method is applied to the reconstruction of an economic space from Exchange-Traded Funds (ETFs) data. In the past, the same method was used in a geometrical analysis of times series of stock returns implying that the most of the systematic information of that market is contained in a space of small dimension. The same dimensional reduction was obtained using daily returns of 85 ETF securities in a time frame of more than 16 years. Having a metric defined in the space of ETF securities, a topological approach is used to define a complete network of ETFs and its corresponding Minimum Spanning Tree (MST). An outstanding separation of the two main classes of securities over the MST is uncovered. The dimensional reduction as well as the uncovered pattern in the topological structure, they both emerge from the data itself rather than from any modelling resolution.

Coordinated Anions Tune Z-Type Ligand Displacement from Colloidal CdSe and InP Nanocrystal Surfaces.

Neutral metal salts coordinate to the surfaces of colloidal semiconductor nanocrystals (NCs) by acting as Lewis acid acceptors for the NC surface anions. This ligand coordination has been associated with increased emission due to the passivation of surface hole traps. Here, variation of the anionic ligands of metal salts is used to study anion effects on metal complex Lewis acidity and surface coordination at CdSe and InP NCs. To resolve dynamic ligand exchange processes, the tetracarbonylcobaltate anion, [Co(CO)4]-, is used as a monoanionic ligand for which IR spectroscopy can readily identify displacement of neutral M[Co(CO)4]x species (M = Cd or In; x = 2 or 3, respectively) upon addition of neutral donor ligands. Notably, although Cd[Co(CO)4]2 is more Lewis acidic than cadmium oleate, the former is more readily displaced from the NC surfaces. Lewis acidity and X-type anion exchange are, therefore, factors to be considered when performing postsynthetic addition of metal salts for NC photoluminescence emission enhancement.

Genetic structure and potential hybridization between populations of two Penstemon species

Abstract Hybridization is a common phenomenon in plants, facilitating genetic exchange and contributing to evolutionary innovation. In Penstemon, which boasts a diverse array of species with varying pollination syndromes, hybridization has been extensively documented. In this study, we employed nine nuclear microsatellites to investigate the genetic differentiation between Penstemon gentianoides and P. roseus populations, along with two populations of potentially hybrid morphotypes. Our results reveal significant genetic differentiation among populations, particularly between sympatric and allopatric populations of P. gentianoides and P. roseus. Bayesian analyses identified three genetic clusters, the first corresponding to individuals of sympatric and allopatric P. roseus populations, and the second and third to intermixed individuals of sympatric and allopatric P. gentianoides populations and intermediate morphotypes. Sympatric populations of both parental species exhibit signs of admixture. Contemporary and historical migration rates were low and asymmetrical among populations, with higher migration rates from the ‘fuchsia’ morphotype to P. gentianoides populations. The significant and positive correlation between migration rates suggests that migration patterns have remained relatively stable over time. These findings underscore the complex dynamics of genetic exchange and hybridization between Penstemon populations, highlighting the need for further research to understand population differentiation in the presence of gene flow.

Closed-Loop Recyclable and Extrusion Reprocessable Thermosets Enabled by Guanylthiourea Structure.

Plastic recycling is a critical step toward improving waste management and achieving economic recycling. Here, a thermoset crosslinked by guanythiourea structure (GTUH network) is reported, that addresses the recycling issue of thermosets by serial hybridization of thiourea and guanidine urea. The dual dissociative dynamic exchange reaction of guanamine urea and thiourea, combined with non-covalent hydrogen bonding interactions, endows the network with rapid relaxation ability. GTUH networks, in particular, can be recycled through continuous extrusion processing due to multiple reversible mechanisms, as opposed to hot pressing alone. Even if reprocessed by hot pressing, only 5 min at 140 °C and 10MPa are required. The oxidation enhancement mechanism of thiourea contributes to maintaining or even improving the mechanical properties of the recycled network. Moreover, the dynamic reactions of guanythiourea structure allow for closed-loop chemical recycling of the network. Research into recyclable carbon fiber-reinforced composites indicates promising potential applications for this material in the circular economy and resources.

Türkiye's Immigration Landscape: Cultural Exchange and Labor Dynamics with Africa

Türkiye’s relations with the African continent trace back to the periods of the Ottoman Empire’s existence there. Beginning with trade, continuing education, and improving labor force requirements continue to strengthen relations with the Modern Türkiye. As a result of the transformations the African continent has undergone in recent years, Türkiye wants to take advantage of the opportunities in the region, increasing its reputation through civil society organizations and aid agencies, while exerting a protective and reassuring influence in the region through military cooperation. Due to factors triggering migration from African countries, Türkiye and Europe are seen as a new hope for immigrants. In addition to the increasing need for the labor force, affordable education, and scholarship opportunities, the university entrance exam prepared specifically for foreign students also makes Türkiye an attractive center. In this article, you will witness the journey stories of hope that often begin with aspirations to become football players, the changes in the perception of Africans over the years through the power of social media, and the factors influencing this, as well as the importance of arts, music, films, and television series in shaping society. From the challenges faced by African communities seeking hope in a new country to the conveniences provided by government institutions during the integration process, all these processes are addressed in this article.

Development of Multiscale Force Field for Actinide (An3+) Solutions.

A multiscale force field (FF) is developed for an aqueous solution of trivalent actinide cations An3+ (An = U, Np, Pu, Am, Cm, Bk, and Cf) by using a 12-6-4 Lennard-Jones type potential considering ion-induced dipole interaction. Potential parameters are rigorously and automatically optimized by the meta-multilinear interpolation parametrization (meta-MIP) algorithm via matching the experimental properties, including ion-oxygen distance (IOD) and coordination number (CN) in the first solvation shell and hydration free energy (HFE). The water solvent models incorporate an especially developed polar coarse-grained (CG) water scheme named PW32 and three widely used all-atom (AA) level SPC/E, TIP3P, and TIP4P water schemes. Each PW32 is modeled as two bonded beads to represent three neighboring water molecules, the simulation efficiency of which is 1 to 2 orders of magnitude higher than that of AA waters. The newly developed FF shows high accuracy and transferability in reproducing the IOD, CN, and HFE of An3+. The molecular structure and water exchange dynamics of the first An3+ hydration shell and the ionic (van der Waals) radii are reinvestigated in this work. Moreover, the new FF can readily be transferred to other popular FFs, as it has practicably predicted the permeability of An3+ in a graphene oxide filter within the framework of optimized potentials for liquid simulations (OPLS)-AA FF. It holds promise for applications in exploring actinide aqueous solutions with multiscale computational overhead.

Hydrogen-Bonded Supramolecular Network Enabled Gentle Reprogramming of Liquid Crystal Elastomer toward Evolutionary Robot.

In nature, many organisms augment chances of survival by reprogramming their structures to evolving environment, among which sea squirts being a prime example. Such reprogramming has been demonstrated in liquid crystal elastomer (LCE) actuator assembled with heat assistance. However, the required temperature being higher than the actuation temperature limits its application. Here, we reported a hydrogen-bonded supramolecular network LCE to construct soft modular and reprogrammable actuator by assembling with a gentle heat treatment. Leveraging the Michael addition reaction, we introduced hydrogen bonding to the LCE matrix with functionalized pyridine monomers. Experimental and molecular dynamics modeling proved the efficient dynamic hydrogen bond exchange at 60 °C, significantly lower than the actuating temperature of the LCE. This gave rise to the reversible and robust adhesion of the same collection of LCE modules capable of being built into different bilayers and performing various morphing upon a short thermal stimulation. Therefore, we demonstrated that these comparatively weak cross-links enabled reconfiguration of the LCE actuator. With the developed hydrogen-bonding LCEs, we built proof-of-concept modular reprogrammable robot, performing crawling, sailing, and microcircuit repair tasks. This bioinspired and efficient method for evolutionary LCE robot offers a viable path for further development of intelligent actuators sustainable in complex environments.

Hydrogen‐Bonded Supramolecular Network Enabled Gentle Reprogramming of Liquid Crystal Elastomer toward Evolutionary Robot

AbstractIn nature, many organisms augment chances of survival by reprogramming their structures to evolving environment, among which sea squirts being a prime example. Such reprogramming has been demonstrated in liquid crystal elastomer (LCE) actuator assembled with heat assistance. However, the required temperature being higher than the actuation temperature limits its application. Here, we reported a hydrogen‐bonded supramolecular network LCE to construct soft modular and reprogrammable actuator by assembling with a gentle heat treatment. Leveraging the Michael addition reaction, we introduced hydrogen bonding to the LCE matrix with functionalized pyridine monomers. Experimental and molecular dynamics modeling proved the efficient dynamic hydrogen bond exchange at 60 °C, significantly lower than the actuating temperature of the LCE. This gave rise to the reversible and robust adhesion of the same collection of LCE modules capable of being built into different bilayers and performing various morphing upon a short thermal stimulation. Therefore, we demonstrated that these comparatively weak cross‐links enabled reconfiguration of the LCE actuator. With the developed hydrogen‐bonding LCEs, we built proof‐of‐concept modular reprogrammable robot, performing crawling, sailing, and microcircuit repair tasks. This bioinspired and efficient method for evolutionary LCE robot offers a viable path for further development of intelligent actuators sustainable in complex environments.

Interpretation of Western Images from a Postcolonial Perspective: A Case Study of Antonioni's Documentary Chung Kuo - Cina

This paper employs textual analysis and postcolonial theory to explore Michelangelo Antonioni's 1972 documentary Chung Kuo - Cina. The study delves into the film's portrayal of Chinese culture, people, and environment, focusing on how these depictions either reinforce or challenge Western audiences' expectations and prejudices. Antonioni's documentary is analyzed for its use of symbolism, cinematographic techniques, and scene selection in constructing an "exotic" image of China. Through a postcolonial lens, the paper examines how the documentary demonstrates Orientalist perspectives, reflecting Western stereotypes and biases towards China. Furthermore, it explores the broader implications of these representations in the context of cultural exchange and power dynamics. The analysis also considers the historical and political backdrop of the film's production, including the Cultural Revolution and China's efforts to shape its international image. This study contributes to a deeper understanding of how visual media shape and disseminate national images in cross-cultural contexts, highlighting the complexities of postcolonial identity construction and the enduring impact of Orientalism in contemporary visual culture.

Audiovisual Imagery in Multimodal Perception and Performance of Qigang Chen’s Er Huang Concerto

In the realm of musical performance, the role of a pianist extends beyond the mere execution of musical scores to become a pivotal contributor to artistic expression. This study delves into the auditory and visual imagination through the perception and performance of piano works by the Chinese-French composer Qigang Chen from the early 21st century, involving the performer’s meticulous response to the nuances of musical sound as well as the interplay of visual synaesthesia.The study also explores the inherent conveyance chain within the performance process, experimenting with multimodal forms of expression. These creative choices not only enrich the narrative of the arts but also contribute to crafting a comprehensive, immersive concert experience for the audience. The principal aim of this research is to explore the prismatic view within Qigang Chen’s piano work, offering multiple possibilities of meaning and emphasizing the crucial role of the pianist in forming and elucidating the fusion of auditory and visual senses in performative action.By transcending traditional performance boundaries, this exploration invites the audience to witness the multimodal interactions inherent in musical performances, providing a fresh perspective on dynamic exchanges between different sensory elements and cultural influences.

Developing the optimized control scheme for digital light processing 3D printing by combining numerical simulation and machine learning-guided temperature prediction

Digital light processing (DLP) 3D printing has attracted significant attention for its rapid printing speed, high accuracy, and diverse applications. However, the continuous DLP printing process releases substantial heat, resulting in a swift temperature rise in the curing area, which may lead to printing failures. Due to the lack of effective means to measure real-time temperature changes of the curing surface during continuous DLP 3D printing, the prevailing approach is to predict temperature variations during printing via numerical simulation. Nevertheless, temperature prediction methods relying solely on numerical simulation tend to be slow and overlook heat exchange dynamics during printing, potentially resulting in prediction inaccuracies, particularly for complex models. To address these issues, this paper proposes a method to combine numerical simulation and a machine learning approach for temperature prediction in the DLP 3D printing process, along with a printing control scheme generation method. Firstly, the m+nth order autocatalytic kinetic model considering the light intensity and the Beer–Lambert law are employed to formulate the heat calculation equation for the photopolymer resin curing reaction. Subsequently, a heat exchange calculation equation is established based on Fourier heat conduction law and Newton’s cooling equation. A numerical simulation model for temperature changes during the printing process is then developed by integrating the heat calculation equation, heat exchange calculation equation, and measurement data from Photo-DSC. Furthermore, a temperature measurement device for the printing process is designed to validate the accuracy of the numerical simulation. Following this, an improved Long Short-term Memory (LSTM) network is proposed, using temperature change data generated by the numerical simulation model to train the network for rapid (2×10−4s/layer) prediction of temperature changes during printing. Finally, aiming for the shortest printing time, an optimized control scheme planning algorithm and a target function are designed based on the model’s temperature change data and the monomer’s flash point to ensure the temperature remains below this threshold. This algorithm can automatically generate the optimal printing control scheme for any model. Experimental results demonstrate that the proposed temperature prediction method can predict temperature variation accurately. Based on this, the generated printing control scheme can guarantee efficient and high-quality manufacturing for anymodel.

Effect of Exchange Dynamics on the NMR Relaxation of Water in Porous Silica.

The interaction of molecules, in particular, water, with solid interfaces has been studied by a multitude of methods, among them nuclear magnetic resonance spin relaxation. The frequency dependence of the relaxation times follows patterns that have been interpreted in terms of the molecular orientation and dynamics. Several different model approaches could successfully explain limiting cases of 1H relaxation dispersion in systems with rigid surfaces such as silica gel or glass, but none of them can reproduce the relaxation of both 1H and 2H nuclei, which differ in their respective relaxation mechanisms, dipolar vs quadrupolar. From detailed studies of the dynamics of hydration of water in biological materials, the importance of hydrogen and molecular exchange to the longitudinal relaxation time of T1 was demonstrated. In this work, exchange times of both H2O and D2O in hydrophilic silica gel are varied in a controlled fashion in a wide range using disodium hydrogen phosphate, and the effect of physical exchange on spin relaxation is quantified for the first time in such systems using the exchange-mediated reorientation model.

19F-Labeled NMR Probes for the Detection and Discrimination of Nitrogen-Containing Analytes

AbstractThe development of 19F-labeled NMR probes has become a pivotal tool in analytical chemistry. Recent advancements in probe design enable precise identification of nitrogen-containing analytes, significantly enhancing the analysis of these biologically important analytes in complex mixtures. This short review highlights recent progress with probes based on covalent derivatization and dynamic exchange strategies, which yield distinct 19F NMR signals for each nitrogen-containing analyte. These strategies facilitate separation-free multicomponent analysis and chiral discrimination. Discussions will cover design principles, scope, limitations, and strategies to enhance the sensitivity and resolving ability. By addressing current challenges, 19F-labeled NMR probes hold the potential to revolutionize the detection of biologically relevant molecules, catalyzing new discoveries in chemical and biochemical research.1 Introduction2 19F-Labeled Probes Based on Covalent Derivatization2.1 Non-Chiral 19F-Labeled Probes Based on Covalent Derivatization2.2 Chiral 19F-Labeled Probes Based on Covalent Derivatization3 19F-Labeled Probes Based on Dynamic Ligand Exchange3.1 Non-Chiral 19F-Labeled Probes Based on Dynamic Ligand Exchange3.2 Chiral 19F-Labeled Probes Based on Dynamic Ligand Exchange4 Conclusion and Outlook

Different effects of cardiomyocyte contractile activity on transverse and axial tubular system luminal content dynamics

BackgroundEfficient excitation-contraction coupling of mammalian ventricular cardiomyocytes depends on the transverse-axial tubular system (TATS), a network of surface membrane invaginations. TATS enables tight coupling of sarcolemmal and sarcoplasmic reticulum membranes, which is essential for rapid Ca2+-induced Ca2+ release, and uniform contraction upon electrical stimulation. The majority of TATS in healthy ventricular cardiomyocytes is composed of transverse tubules (TT, ∼90 % of TATS in rabbit). The remainder consists of mostly axial tubules (AT), which are less abundant and less well studied. In disease, however, the relative abundance of TT and AT changes. The mechanisms and relevance of this change are not known, and understanding them requires a more targeted effort to study the dynamics of AT structure and function.While TATS content is continuous with the interstitial space, it is contained within a domain of restricted diffusion. We have previously shown that TT are cyclically squeezed during stretch and contraction. This can contribute to TT content mixing and accelerates luminal content exchange with the environment. Here, we explore the effects of cardiomyocyte stretch and contraction on AT. MethodsTATS structure and diffusion dynamics were studied using 3D electron tomography of rabbit left ventricular cardiomyocytes, preserved at rest or during contraction, and ventricular tissue preserved at rest or during stretch, as well as live-cell TATS content exchange measurements. ResultsWe show (i) that cardiomyocyte contraction is associated with an increase in the apparent speed of diffusion of TT content that scales with beating rate and degree of cell shortening. In contrast, (ii) AT develop membrane folds and constrictions during contraction, (iii) with no effect of contraction on luminal exchange dynamics, while (iv) cardiomyocyte stretch is associated with AT straightening and AT and TT ‘squeezing’ that (v) supports an acceleration of the apparent speed of diffusion in AT and TT. Finally, (vi) we present a simple computational model outlining the potential relevance of AT in healthy and diseased cells. ConclusionsOur results indicate that TT and AT are differently affected by the cardiac contractile cycle, and suggest that AT may play a role in ensuring TATS network content homogeneity in diseased cardiomyocytes. Further research is needed to explore the interplay of structural and functional remodelling of different TATS components in failing myocardium.