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A novel inorganic‐organic‐inorganic ternary bioactive material formulated on antimicrobial peptide‐based polymer has been reported. Supramolecular approach has been employed to incorporate molecularly crowded tyrosine‐based polymer stabilized silver nanoparticles into membrane bound vesicles exploiting polyoxometalate‐triggered surface templating strategy. Utilizing the covalent reversible addition fragmentation chain transfer (RAFT) polymerization and exploiting templated supramolecular architectonics at biopolymer interface, the bioactive ternary polymeric nanohybrids have been designed against Shigellosis leveraging the antibacterial activities of silver nanoparticle, cationic amphiphilic tyrosine polymer and inorganic polyoxometalate. The detail investigation against Shigella flexneri 2a cell line demonstrates that the collaborative mechanism of the ternary hybrid composite enhances the bactericidal activity in comparison to only polyoxometalate and polymer stabilized silver nanoparticle with an altered mechanism of action which is established via detailed biological analysis. [ABSTRACT FROM AUTHOR]

Smart polymers undergo significant physical or chemical changes in response to stimuli like temperature and pH. Achieving a narrow molecular weight distribution is crucial for their sensitivity. Reversible addition–fragmentation chain transfer (RAFT) in ionic liquids is an effective method for synthesizing such polymers due to its favorable kinetics and environmental benefits. Most studies use imidazolium ionic liquids, while pyridinium ionic liquids are less common despite their easy synthesis. This study reports the first successful RAFT copolymerization of di(ethylene glycol) methyl ether methacrylate (DEGMEMA) and methyl methacrylate in N‐hexylpyridinium hexafluorophosphate ([HPY][PF6]). Both linear and hyperbranched copolymers (Mn > 25,000) with narrow molecular weight distribution were synthesized, showing observable temperature responses and biocompatibility. The linear copolymers had a desirable dispersity (Ð) of less than 1.10, while the hyperbranched copolymer had a Ð of 2.034. The lower critical solution temperatures (LCSTs) of the copolymers were close to or below the LCST of PDEGMEMA (26°C). This study indicates that pyridinium ionic liquids can be explored as a suitable solvent for synthesizing methacrylate‐based smart polymers. [ABSTRACT FROM AUTHOR]

Reversible addition–fragmentation chain transfer (RAFT) emulsion polymerization of methyl methacrylate (MMA) is successfully performed in water in the presence of a poly(methacrylic acid) (PMAA) macromolecular chain transfer agent (macroCTA) leading to the formation of self‐stabilized PMAA‐b‐PMMA amphiphilic block copolymer particles. At pH 3.7, the reactions are well‐controlled with narrow molar mass distributions. Increasing the initial pH, particularly above 5.6, results in a partial loss of reactivity of the PMAA macroCTA. The effect of the degree of polymerization (DPn) of the PMMA block, the solids content, the nature of the hydrophobic segment, and the pH on the morphology of the obtained diblock copolymer particles is then investigated. Worm‐like micelles are formed for a DPn of PMMA of 20 (PMMA20), while "onion‐like" particles and spherical vesicles are obtained for PMMA30 and PMMA50, respectively. In contrast, spherical particles are obtained for the DPns higher than 150. This unusual evolution of particle morphologies upon increasing the DPn of the PMMA block seems to be related to hydrogen bonds between hydrophilic MAA and hydrophobic MMA units. [ABSTRACT FROM AUTHOR]

Nanomedicine is a discipline of medicine that applies all aspects of nanotechnology strategies and concepts for treatment and screening possibilities. Synthetic polymer nanostructures are among the many nanomedicine formulations frequently studied for their potential as vectors. Bioimaging is a valuable diagnostic tool, thus, there is always a demand for new excipients/nanocarriers. In this study, hydrophobic hyperbranched poly(lauryl methacrylate) (PLMA) homopolymers comprised of highly hydrophobic LMA moieties with –COOH polar end groups were synthesized by employing reversible addition-fragmentation chain transfer (RAFT) polymerization. Ethylene glycol dimethacrylate (EGDMA) was utilized as the branching agent. End groups are incorporated through the RAFT agent utilized. The resulting amphiphilic hyperbranched polymer was molecularly characterized by size exclusion chromatography (SEC), Fourier transformation infrared spectroscopy (FT–IR), and 1H–NMR spectroscopy. Pyrene, curcumin, and IR-1048 dye were hydrophobic payload molecules successfully encapsulated to show how adaptable these homopolymer nanoparticles (prepared by nanoprecipitation in water) are as dye nanocarriers. This study demonstrates a simple way of producing excipients by generating polymeric nanoparticles from an amphiphilic, hyperbranched, hydrophobic homopolymer, with a low fraction of polar end groups, for bioimaging purposes. [ABSTRACT FROM AUTHOR]

Ground losses due to tunneling would induce settlement of nearby raft foundations. To study the change in behavior of the raft foundations over time due to tunnel excavation in soft clay, a series of centrifuge model tests were conducted. The results reveal that the raft stiffness has a significant influence on the development of the gap between the raft and the ground. The width of the gap beneath the flexible foundation would increase over time, leading to a further increase in tensile strain after excavation, whereas the gap for raft foundations with a large stiffness would reduce with time, causing a gradual decrease in tensile strain. The modification factor (MF) design approach is also evaluated with the test results and demonstrates that the MF design approach would underestimate the tensile strain of the flexible raft and provide a relatively conservative prediction for larger stiffnesses. [ABSTRACT FROM AUTHOR]

In this study, we report the synthesis of 3‐, 4‐, and 6‐arm star poly(ionic liquid)s (PILs) (specifically, star poly(vinylbenzyl methylimidazolium bis(trifluoromethane)sulfonimide) (poly(VBMIm‐TFSI))) via reversible addition‐fragmentation chain transfer (RAFT) polymerization with a core‐first approach, followed by quaternization and anion exchange. The impact of star polymer architecture on properties was explored by measuring the thermal, mechanical, and ion transport properties of each star PIL compared to those of an analogous linear PIL. The star PILs exhibited up to 2‐fold higher ionic conductivity, 150% higher elastic modulus, and 465% higher ultimate tensile strength compared to the analogous linear PIL. The Williams‐Landel‐Ferry (WLF) equation was employed to explore the effect of increased free volume on the improved ion transport properties of the star PILs. These results highlight the impact of star polymer architecture on PILs and star PILs as promising materials for electrochemical energy devices. [ABSTRACT FROM AUTHOR]

In this research, we explored the synthesis and application of thiolactone acrylamide (TLA) polymers for neutralizing reactive oxygen species (ROS), produced as a result of traumatic brain injury (TBI). We synthesized well‐defined TLA polymers using RAFT (reversible addition‐fragmentation chain transfer) polymerization across a range of monomer‐to‐chain transfer agent ([M]0/[CTA]0) ratios to achieve a range of molar masses. Polymerizations were carried out using a trithiocarbonate CTA (chain transfer agent) with AIBN (azobisisobutyronitrile) as the initiator in N'N‐dimethylacetamide (DMAc) at 60 °C. Kinetic studies indicated a linear increase in molar mass with conversion, pseudo‐first‐order kinetics, and molar mass values that are consistent with theoretical predictions. Furthermore, the polymerizations exhibited a decrease in molar mass dispersity with conversion. We then investigated ring opening of the thiolactone residues with isoserinol (ISOH), which was followed by thiol‐ene reactions of the resultant thiol groups with methacrylamide to yield a series of copolymers with different thiol‐to‐thioether ratios. The resulting polymers demonstrated varying levels of ROS neutralization. Higher thiol concentrations lead to more rapid neutralization while thioether residues provided sustained neutralization activity. [ABSTRACT FROM AUTHOR]

Currently, Raft, as an mainstream consensus mechanism, has received widespread attention. Partition consensus can reduce the number of nodes involved in a single consensus and improve consensus efficiency. However, existing algorithms suffer from unreasonable partitioning and intolerance of Byzantine nodes. To address these problems, this paper proposes a novel Raft consensus algorithm combining comprehensive evaluation partitioning and Byzantine fault tolerance, CB-Raft. First, a comprehensive evaluation of nodes is conducted from the perspectives of consensus behavior and location, and the nodes are evenly divided based on the parity of the comprehensive ranking. Second, the leader is selected from the nodes with the top rankings in the comprehensive evaluation, and the nodes communicate with each other based on BLS signatures. Finally, a fast response mechanism based on cross-partition leader-follower communication is proposed to avoid the continued evil behavior of the leader, and a pipeline mechanism based on changeable signature thresholds is proposed to solve consensus blocking. The experimental results show that compared with the existing partitioning methods, the proposed partitioning scheme has significant advantages in terms of consensus latency, throughput, and the probability of partition success. Compared with the similar Raft algorithms, CB-Raft has high consensus performance and good resistance to Byzantine nodes. [ABSTRACT FROM AUTHOR]

Abstract This comprehensive review provides a detailed examination of controlled polymerization in the development of nanogels‐based microfluidic devices. Here, we have explored the integration of atom transfer radical polymerization (ATRP) and reversible addition‐fragmentation chain transfer (RAFT) techniques within microfluidic platforms for the synthesis of nanogels. The synergistic combination of ATRP and RAFT with microfluidics has emerged as a powerful tool for precise control over polymerization reactions, enabling the fabrication of well‐defined, multifunctional nanogels with tailored properties. The review begins with a thorough introduction to the principles of ATRP and RAFT, highlighting their respective advantages in controlled radical polymerization. Subsequently, it elucidates the principles of microfluidics and its profound impact on polymerization processes. The merging of these techniques enables precise control over reaction kinetics, monomer conversions, and molecular weight distributions, facilitating the synthesis of nanogels with unprecedented precision and reproducibility. Furthermore, this review delves into the chemical mechanisms underlying ATRP and RAFT reactions in microfluidic environments, emphasizing the role of various initiators, catalysts, and chain transfer agents. Special attention is given to the impact of microscale flow conditions on reaction kinetics and polymer structure. In addition, the review discusses emerging trends in the field, such as the incorporation of novel monomers and the exploration of environmentally benign reaction conditions. Highlights The controlled polymerization is the mechanism by which we can obtain tailormade material. The nanogel synthesis must ensure the gelation to be in confined dimensions here microfluidics plays key role.

Light‐mediated 3D printing techniques have gained significant interest due to the inherent advantages of light as external stimuli, including spatiotemporal control and easy access. As 3D printing processes require rapid polymerization, free radical or cationic polymerization methods are used. However, these polymerization reactions are limited to the production of materials with properties that cannot be chemically altered post‐printing. In this work, a rapid, open‐to‐air photo‐controlled cationic reversible addition‐fragmentation chain‐transfer polymerization of vinyl ethers is demonstrated in the presence of a three‐component photoinitiating system comprising a photosensitizer, electron donor, and acceptor as co‐initiators under the irradiation with blue light. The polymerization mechanism shows rapid kinetics and controlled, living polymerization characteristics. Trithiocarbonate chain ends of poly(isobutyl vinyl ethers) are reactivated to produce block copolymers with cyclohexyl vinyl ethers. The rapid kinetics and water tolerance of the reported system enable the 3D printing of polymeric solids under ambient (e.g., room temperature and open to air) conditions, followed by the effective reactivation of trithiocarbonate chain ends to post‐synthetically modify the object with an acrylate‐based fluorescent monomer via a controlled radical polymerization strategy. [ABSTRACT FROM AUTHOR]

This study introduces bis(1‐cyanocyclohex‐1‐yl)trithiocarbonate (TTC‐bCCH) as a novel trithiocarbonate chain transfer agent and compares its reactivity with the previously described bis(2‐cyanopropan‐2‐yl)trithiocarbonate (TTC‐bCP) for the reversible addition‐fragmentation chain transfer (RAFT) polymerization of styrene (St), n‐butyl acrylate (nBA), and methyl methacrylate (MMA). Significant findings include the effective control of Mn and low dispersities from the onset of polymerization of St and nBA showing swift addition‐fragmentation kinetics, leading to similar behaviors between the two RAFT agents. In contrast, a fourfold decrease of the chain transfer constant to MMA is established for TTC‐bCCH over TTC‐bCP. This trend is confirmed through density functional theory (DFT) calculations. Finally, the study compares thermoplastic elastomer properties of all‐(meth)acrylic ABA block copolymers produced with both RAFT agents. The impact of dispersity of PMMA blocks on thermomechanical properties evaluated via rheological analysis reveals a more pronounced temperature dependence of the storage modulus (G′) for the triblock copolymer synthesized with TTC‐bCCH, indicating potential alteration of the phase separation. [ABSTRACT FROM AUTHOR]

Amphiphilic block copolymers of poly(ethylene glycol) (PEG) and poly(vinylidene fluoride) (PVDF) were successfully synthesized by growing poly(vinylidene fluoride) on PEG‐chain transfer agent (PEG‐macro‐CTA) using reversible addition–fragmentation chain transfer (RAFT) polymerization. MeO‐PEG‐XA, and XA‐PEG‐XA macro‐CTAs (XA refers to the xanthate moiety), synthesized by esterification of MeO‐PEG‐OH (20,000 g mol−1) and HO‐PEG‐OH (20,000 g mol−1) with 2‐bromopropionyl bromide followed by reaction with potassium ethyl xanthate, were used to synthesize MeO‐PEG‐b‐PVDF and PVDF‐b‐PEG‐b‐PVDF, respectively. The synthesized macro‐CTAs and block copolymers were characterized by NMR (1H, 13C and 19F), FTIR, and SEC. Furthermore, the PVDF/PEG block copolymer formation was proved by 1H DOSY NMR. The thermal properties were determined by TGA and DSC. The crystallinity and electroactive phases were revealed by XRD and FTIR. The size and shape of self‐assembled block copolymers in DMF/water mixtures were determined by DLS, TEM and critical micelle concentration with fluorescence spectroscopy. The influence of molecular weight and PVDF content on the properties of copolymers is discussed. [ABSTRACT FROM AUTHOR]

Anthropogenic activities have denatured aquatic, terrestrial, and aerial environments throughout the world in general, and in Lubumbashi in particular, where market garden soils have become uncultivable for many plants. Thus, bioponics could be an effective means of producing uncontaminated vegetables in soilless cultivation, not only reducing the amount of fertilizer used and limiting contamination of agricultural produce but also achieving higher yields than in open-ground cultivation. The overall objective of this study was to implement a new bioponic technique for producing liquid fertilizer from chicken manure and utilize it in the organic hydroponic cultivation of lettuce (Lactuca sativa var. Lucrecia) installed on floating raft systems. To achieve this, two types of trials were conducted. The first was aimed at determining the quantities of organic matter to be used in the formulation of nutrient solutions. The second trial aimed to determine the optimal nitrogen concentration to be provided for hydroponic plant growth. Mineralization and/or anaerobic digestion of chicken manure were conducted for 7 days in 200 L barrels. For the first trial, nutrient solutions were created from three different concentrations of chicken manure (0.35%, 3.5%, and 7% dry matter—D.M.). These solutions were then used in bioponic rafts where total ammonia nitrogen (TAN) concentrations were fixed at 150 mg/L. For the second trial, D.M. was fixed at 2.5% for each tested modality, but TAN concentrations varied among them (i.e., 60, 90, and 120 mg/L TAN concentration). Modalities with low D.M. concentration (0.35%) and those with low TAN concentration (60 mg/L) resulted in higher yields than bioponic modalities receiving high concentrations of dry matter or TAN, respectively, for trials 1 and 2. Although the reference chemical solutions generate the greatest yields, bioponic systems operating with chicken manure present a good alternative for the cultivation of vegetables in developing countries with heavily contaminated soils. Indeed, bioponics allows for the production of vegetables in large quantities from animal waste, which does not pose health risks for human consumption. Local vegetable species commonly grown in Lubumbashi should be tested under hydroponic conditions. [ABSTRACT FROM AUTHOR]

Reversible addition‐fragmentation chain‐transfer (RAFT) polymer networks grow in interest due to their living and tunable characteristics. An essential step toward exploiting these characteristics is the production of precise patterns for growth. Herein, a novel, straightforward strategy to produce patterns to control growth on RAFT‐based living polymer networks (LPNs) is presented. A 405 nm laser is used to degrade the RAFT agents in selected regions, generating a pattern. This occurs through homolytic photocleavage at the C─S bond, leading to the typical RAFT equilibrium state with the R‐group radical and a thiyl radical species, followed by irreversible loss of CS2 to produce a Z‐group derived thiol. Using this technique, both "on/off" patterns and more detailed greyscale patterns are produced using images of varying complexity. Post production growth then shows that these patterns are visually retained after iniferter growth with a fluorescent monomer. Due to the deactivation of selected RAFT agents, the authors are able to perform discriminate growth with network‐wide irradiation. This selective degradation technique serves as an alternative technique for producing patterns on RAFT LPNs. [ABSTRACT FROM AUTHOR]

This paper proposed a dual-layer consensus algorithm (DL_RBFT) based on the enhanced Raft and practical Byzantine fault tolerance (PBFT) consensus algorithms to address scalability issues, excessive communication overhead, and challenges in large-scale network node environments in use within consortium blockchains. Initially, it divided blockchain nodes into several groups to form a lower-layer consensus network. Then, leaders from these groups constituted an upper-layer consensus network, creating a dual-layer consensus structure. In the lower-layer consensus network, it improved Raft consensus algorithm by introducing supervision and reputation mechanisms, while the leader election process introduced ant colony optimization to maintain high efficiency. In the upper-layer consensus network, it utilized the PBFT consensus algorithm for consensus. The enhanced Raft consensus algorithm exhibited resistance to Byzantine node attacks, enhancing the algorithm’s security. Experimental results indicate that compared to traditional PBFT consensus algorithms, DL_RBFT reduces consensus latency by two orders of magnitude and improves throughput by one order of magnitude in a 100-node scenario. In comparison to other enhanced algorithms, DL_RBFT demonstrates significant advantages. Therefore, DL_RBFT consensus algorithm exhibits strong scalability and can be widely applied in various consortium blockchain scenarios. [ABSTRACT FROM AUTHOR]

This comprehensive review provides a detailed examination of controlled polymerization in the development of nanogels‐based microfluidic devices. Here, we have explored the integration of atom transfer radical polymerization (ATRP) and reversible addition‐fragmentation chain transfer (RAFT) techniques within microfluidic platforms for the synthesis of nanogels. The synergistic combination of ATRP and RAFT with microfluidics has emerged as a powerful tool for precise control over polymerization reactions, enabling the fabrication of well‐defined, multifunctional nanogels with tailored properties. The review begins with a thorough introduction to the principles of ATRP and RAFT, highlighting their respective advantages in controlled radical polymerization. Subsequently, it elucidates the principles of microfluidics and its profound impact on polymerization processes. The merging of these techniques enables precise control over reaction kinetics, monomer conversions, and molecular weight distributions, facilitating the synthesis of nanogels with unprecedented precision and reproducibility. Furthermore, this review delves into the chemical mechanisms underlying ATRP and RAFT reactions in microfluidic environments, emphasizing the role of various initiators, catalysts, and chain transfer agents. Special attention is given to the impact of microscale flow conditions on reaction kinetics and polymer structure. In addition, the review discusses emerging trends in the field, such as the incorporation of novel monomers and the exploration of environmentally benign reaction conditions. Highlights: The controlled polymerization is the mechanism by which we can obtain tailormade material.The nanogel synthesis must ensure the gelation to be in confined dimensions here microfluidics plays key role. [ABSTRACT FROM AUTHOR]

Empagliflozin (EMP) is known for its poor safety and efficacy profile due to its fast body distribution and poor solubility. Accordingly, an oral long-acting and floating/raft-forming nano gel was optimized to release coated EMP nanoparticles, and the released EMP nanoparticles showed enhanced dissolution compared to raw EMP particles. To repurpose EMP for cancer treatment, EMP shows anti-cancer and anti-inflammatory effects against cancer cells. EMP nanoparticles were characterized using FT-IR, PXRD, SEM, EMP encapsulation assay, and release studies. The raft-forming gel encapsulating the EMP was optimized and characterized. The EMP co-polymeric nanoparticles were studied to investigate EMP anti-cancer and anti-inflammatory activities against stomach cancer cells. The solubility of EMP nanoparticles was enhanced in 0.1 N HCl and pH 6.8 by 5 and 12 folds, respectively, compared to raw EMP powder. The particle size and zeta-potential values of improved EMP nanoparticles were 135.40 ± 18.60 nm, and −19.30 ± 0.80 mV, respectively. FT-IR, PXRD, SEM and TEM characterizations revealed polymeric coating of EMP particles. The study suggested that this optimized controlled-release raft-forming gel is a promising local oral approach against stomach cancer. The repurposing of EMP co-polymeric nanoparticles for stomach cancer and associated gastritis treatment was justified.

The effect of geocell-reinforced cushion on load distribution and settlement reduction in unconnected piled raft foundations was investigated. Modeling and analysis of various scenarios were carried out using Abaqus software. In this research, a total of nine models, including one connected, three unconnected and unreinforced, and five unconnected and reinforced with geocell, were analyzed. Cushions with thicknesses half of, equal to, and twice that of the foundation were used. The results have shown that optimal outcomes in terms of load distribution efficiency and settlement reduction are achieved when the cushion's stiffness is set at half that of the foundation. The obtained results demonstrate the positive effect of geocell reinforcement in enhancing the performance of unconnected piled raft foundations. The introduction of geocells into the models increases soil stiffness and pile load ratio, consequently enhancing the load-bearing capacity of the piled raft foundation compared to the unreinforced models. The study's findings pave the way for a more effective use of geocells in civil engineering applications, particularly in scenarios demanding high load-bearing capacity and minimal foundation settlement.

A series of poly(lauryl methacrylate)-poly(ethyl methacrylate) (PLMA-PEMA) diblock copolymer nano-objects were prepared via reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization in n-heptane at 65 °C. By using PLMA with a fixed degree of polymerization (DP) of 18 as a steric stabilizer block, polymerization of EMA at relatively high concentrations (15% w/w solids or above) allowed for the production of nano-objects with morphologies of sphere, worm and vesicle. Interestingly, at lower concentrations, the diblock copolymer could form unusual structures: micrometer-sized rods and nanotubes at 10% and 7.5% w/w solids, respectively. The SEM and TEM characterization suggests that the rods are kinetically trapped aggregates of worms and spheres, and the formation of nanotubes is presumably due to the fusion of ellipsoidal vesicles and then the shear force exerted by stirring which may trigger the elongation of the vesicles to form the nanotubes. Besides, the diblock copolymer worms exhibited thermoresponsive behavior on heating to 90 °C due to the change in nano-object morphology from worms to spheres. [ABSTRACT FROM AUTHOR]

To assess visually and quantitatively the contributions of the adhesive layer photopolymerization and the subsequent resin composite increment to spatio-temporal maps of temperature at five different cavity locations, subjected to two irradiance curing protocols: standard and ultra-high. Caries-free molars were used to obtain 40, 2 mm thick dentin slices, randomly assigned to groups (n = 5). These slices were incorporated within 3D-printed model cavites, 4 mm deep, restored with Adhese® Universal bonding agent and 2 mm thick Tetric® Powerfill resin composite, and photocured sequentially, as follows: G1: control-empty cavity; G2: adhesive layer; G3 composite layer with no adhesive; and G4 composite layer with adhesive. The main four groups were subdivided based on two curing protocols, exposed either to standard 10 s (1.2 W/cm2) or Ultra high 3 s (3 W/cm2) irradiance modes using a Bluephase PowerCure LCU. Temperature maps were obtained, via a thermal imaging camera, and numerically analyzed at 5 locations. The data were analyzed using two-way ANOVA followed by multiple one-way ANOVA, independent t-tests and Tukey post-hoc tests (α = 0.05). T max , ΔT, T int (integrated area under the curve) and time-to-reach-maximum-temperature were evaluated. Two-way ANOVA showed that there was no significant interaction between light-curing time and location on the measured parameters (p > 0.05), except for the time-to-reach-maximum-temperature (p < 0.05). Curing the adhesive layer alone with the 10 s protocol resulted in a significantly increased pulpal roof temperature compared to 3 s cure (p < 0.05). Independent T-tests between G3 and G4, between 3 s and 10 s, confirmed that the adhesive agent caused no significant increases (p > 0.05) on the measured parameters. The ultra-high light-curing protocol significantly increased ΔT in composite compared to 10 s curing (p < 0.05). When the adhesive layer was photocured alone in a cavity, with a 2 mm thick dentin floor, the exothermal release of energy resulted in higher temperatures with a 10 s curing protocol, compared to a 3 s high irradiance. But when subsequently photocuring a 2 mm layer of composite, the resultant temperatures generated at pulpal roof location from the two curing protocols were similar and therefore there was no increased hazard to the dental pulp from the immediately prior adhesive photopolymerization, cured via the ultra-high irradiation protocol. [ABSTRACT FROM AUTHOR]

The understanding of the complex soil–pile–raft interaction and their mobilization with the level of settlement is an important aspect for the performance-based design of the combined pile–raft foundation (CPRF). This paper investigates the influence of various interactions governing the load-bearing mechanism of a vertically loaded CPRF using a three-dimensional finite element-based computer program. The soil was modeled using the conventional Mohr–Coulomb elastic-perfectly plastic constitutive relationship and the drained condition was adopted in the analysis. Piles and raft were modeled using embedded beam elements and plate elements respectively. After successful validation of the developed numerical model, extensive numerical simulations were carried out considering a CPRF of different geometries and configurations where the foundation was subjected to incremental settlement boundary conditions. The variation of pile–pile, pile–raft and raft–pile interactions with settlement and their influence in dictating the loads induced within the foundation components were obtained. The analysis results indicated that the settlement levels played an important role in the mobilization of loads and dictating the efficiency of CPRF. Piles within a CPRF were able to mobilize their full capacity at the settlement of 1.5–2% of the raft width. The level of settlement and the spacing between the piles dictated the transition from negative interaction to positive interaction indicating a higher capacity of a CPRF compared to the combined capacities of piles and raft at higher settlement levels. Results suggested the operating settlement of CPRF which may be useful for geotechnical practitioners in making this foundation a cost-effective foundation choice. [ABSTRACT FROM AUTHOR]

Metallopolymers with precise structures and particular properties have emerged as promising functional materials. The applications of metallopolymers depend on the unique characteristics of the metal centers (such as electronic, optical, magnetic, redox, etc.) and the superior mechanical and processing performances of classical polymers. Access to accurately design metallopolymers with well-defined structures and chemical compositions has enabled researchers to detailedly investigate their performances and a series of advanced applications. Along with the rapid development of modern synthetic chemistry and polymerization techniques, various functional metallopolymers have been synthesized largely and have shown many potential applications. Especially, controlled polymerizations, including ATRP, RAFT, ROMP, living anionic polymerization, and so on, are currently attracting considerable attention for the synthesis of well-defined metallopolymers. These polymerizations have become versatile and powerful synthetic tools, which enable the synthesis of new metallopolymers with accurately controlled molecular weight, relatively narrow molecular weight distribution, composition (block, graft, alternating gradient copolymers), and various functionalities. In this review, we highlight the most recent progress on the controlled synthesis of various well-defined metallopolymers. The review summarizes the recent progress on controlled polymerizations (such as ATRP, RAFT, ROMP, living anionic polymerization, etc.) for various well-defined metallopolymers, and these polymerizations enable the synthesis of novel metallopolymers with accurately controlled molecular weight, relatively narrow molecular weight distribution, composition (block, graft, alternating gradient copolymers), and diverse functionalities. [ABSTRACT FROM AUTHOR]

Interpenetrating polymer networks (IPNs), comprised of two or more independent crosslinked networks in which the individual networks are interlaced, can be used to enhance material properties and increase functionality for applications such as tissue engineering, drug delivery, and biofabrication. IPNs can be formed by either simultaneous or sequential crosslinking, with sequential crosslinking being complicated by the need to infiltrate the constituents of the second network into the first network. Herein, the study reports the first simultaneous IPN based on the cationic ring‐opening polymerization (CROP) of 2‐methyl‐2‐oxazoline (MeOx) with bis(butyl‐2‐oxazoline) (BBOx) crosslinker and the reversible addition‐fragmentation chain‐transfer (RAFT) polymerization of N,N‐dimethylacrylamide (DMAAm) with N,N'‐methylene bis(acrylamide) (BAM) crosslinker. Specifically, the compatibility of the synthesis techniques is demonstrated for the preparation of simultaneous IPNs, and it is shown that, by varying the amounts of the two crosslinkers and comparing to single‐component networks, the equilibrium degree of swelling (EDS) in water and compressive modulus can be tuned. The results reported demonstrate the utility of CROP and RAFT for preparing IPNs and suggest that with appropriate optimization the technique can be expanded to other monomer pairs which are polymerizable via CROP and RAFT. [ABSTRACT FROM AUTHOR]

Deep swamp is swampland with the longest flooding period, making it challenging for crop cultivation. However, by adopting a floating system, this prolonged duration of flooding can be used for shallot growing. Thus, this study aimed to ascertain the growth and yield of shallots cultivated in polybags using conventional nonfloating and floating systems with the application of different doses of cow manure. The research was located in the experimental field and reservoir of the Faculty of Agriculture, Sriwijaya University (3°13'30.3" S; 104°38'55.1" E). Nonfloating and floating farming systems were utilized with the application of 0, 10, 15 and 20 ton/ha of cow manure. The findings demonstrated that shallots cultivated in the floating system had lower numbers and length of leaf but could produce more bulbs in comparison to the conventional method. The application of 15 ton/ha manure in the floating system resulted in higher weights of fresh and airdried bulbs per plant, weighing 74.40 g and 64.82 g, respectively, compared to those in the nonfloating system (46.77 g and 37.84 g, respectively). In conclusion, the Bima Brebes shallot variety potentially can be cultivated in a floating system with the application of 15 tons of cow manure per hectare. [ABSTRACT FROM AUTHOR]

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Abstract Reversible addition‐fragmentation chain‐transfer (RAFT) polymer networks grow in interest due to their living and tunable characteristics. An essential step toward exploiting these characteristics is the production of precise patterns for growth. Herein, a novel, straightforward strategy to produce patterns to control growth on RAFT‐based living polymer networks (LPNs) is presented. A 405 nm laser is used to degrade the RAFT agents in selected regions, generating a pattern. This occurs through homolytic photocleavage at the C─S bond, leading to the typical RAFT equilibrium state with the R‐group radical and a thiyl radical species, followed by irreversible loss of CS2 to produce a Z‐group derived thiol. Using this technique, both “on/off” patterns and more detailed greyscale patterns are produced using images of varying complexity. Post production growth then shows that these patterns are visually retained after iniferter growth with a fluorescent monomer. Due to the deactivation of selected RAFT agents, the authors are able to perform discriminate growth with network‐wide irradiation. This selective degradation technique serves as an alternative technique for producing patterns on RAFT LPNs.

Nanomedicine is a discipline of medicine that applies all aspects of nanotechnology strategies and concepts for treatment and screening possibilities. Synthetic polymer nanostructures are among the many nanomedicine formulations frequently studied for their potential as vectors. Bioimaging is a valuable diagnostic tool, thus, there is always a demand for new excipients/nanocarriers. In this study, hydrophobic hyperbranched poly(lauryl methacrylate) (PLMA) homopolymers comprised of highly hydrophobic LMA moieties with –COOH polar end groups were synthesized by employing reversible addition-fragmentation chain transfer (RAFT) polymerization. Ethylene glycol dimethacrylate (EGDMA) was utilized as the branching agent. End groups are incorporated through the RAFT agent utilized. The resulting amphiphilic hyperbranched polymer was molecularly characterized by size exclusion chromatography (SEC), Fourier transformation infrared spectroscopy (FT–IR), and 1H–NMR spectroscopy. Pyrene, curcumin, and IR-1048 dye were hydrophobic payload molecules successfully encapsulated to show how adaptable these homopolymer nanoparticles (prepared by nanoprecipitation in water) are as dye nanocarriers. This study demonstrates a simple way of producing excipients by generating polymeric nanoparticles from an amphiphilic, hyperbranched, hydrophobic homopolymer, with a low fraction of polar end groups, for bioimaging purposes.

The biocompatibility, biodegradability, and responsiveness of poly(β‐amino esters) (PBAEs) has led to their widespread use as biomaterials for drug and gene delivery. Nonetheless, the step‐growth polymerization mechanism that yields PBAEs limits the scope for their structural optimization toward specific applications because of limited monomer choice and end‐group modifications. Moreover, to date the post‐synthetic functionalization of PBAEs has relied on grafting‐to approaches, challenged by the need for efficient polymer–polymer coupling and potentially difficult post‐conjugation purification. Here a novel grafting‐from approach to grow reversible addition–fragmentation chain transfer (RAFT) polymers from a PBAE scaffold is described. This is achieved through PBAE conversion into a macromolecular chain transfer agent through a multistep capping procedure, followed by RAFT polymerization with a range of monomers to produce PBAE–RAFT hybrid triblock copolymers. Following successful synthesis, the potential biological applications of these ABA triblock copolymers are illustrated through assembly into polymeric micelles and encapsulation of a model hydrophobic drug, followed by successful nanoparticle (NP) uptake in breast cancer cells. The findings demonstrate this novel synthetic methodology can expand the scope of PBAEs as biomaterials. [ABSTRACT FROM AUTHOR]

In this paper, a real-time optical flow estimation method based on a cross-stage network is proposed. The proposed model is designed with a network structure with encoders and decoders. The proposed method combines cross-stage network technology with the network structure of FlowNet2 and RAFT to achieve improved parameter number and estimation performance. For real-time optical flow estimation, it is important to maintain performance while reducing the number of parameters in the network. In the proposed method, structural convergence is performed to increase performance while reducing the number of parameters by applying the cross-stage network structure. The proposed model is designed to solve the bottlenecks in model accuracy and complexity by separating feature extraction and flow estimation processes. Flying Chairs, Flying Things 3D, and KITTI datasets were used to evaluate the performance of the proposed model, and the experimental results show superior performance compared to previous traditional methods. [ABSTRACT FROM AUTHOR]

We describe the synthesis of a novel series of amphiphilic methacrylate copolymers composed of one hydrophobic monomer carrying a cyclohexyl group and one hydrophilic monomer carrying a short poly(ethylene glycol) chain comprising 6, 9, or 19 units. RAFT polymerization was used to yield well‐defined polymers. First, we studied the kinetic of this copolymerization and calculated the reactivity ratios according to different linear least‐squares (LLS) methods. We thus could demonstrate the statistical copolymerization of the two monomers. Then, by varying the ratio of each monomer in the copolymerization, we developed a series of polymers that were tested for their abilities to extract membrane proteins from Escherichia coli cells overexpressing the Bacillus subtilis multidrug resistance ABC transporter (BmrA) and to stabilize the light‐driven proton transporter bacteriorhodopsin (bR). While our copolymers failed to directly extract significant amounts of proteins, they were found to provide stabilizing environments for extracted membrane proteins, suggesting they could be used as non‐ionic stabilizing polymers. [ABSTRACT FROM AUTHOR]

The consensus mechanism is a critical technology in the power trading blockchain distributed power trading platforms, which are gradually being applied and promoted to achieve the "dual carbon" goal. Green-certificate trading and carbon emission trading systems help mobilize power generation enterprises to increase the generation of and investment in renewable energy, thereby becoming important factors in distributed power trading. Therefore, they should also be considered as factors in the consensus mechanism. This article first evaluates the green-certificate weight based on whether nodes possess green certificates, evaluates the carbon emission weight based on the carbon emission settlement of nodes in the previous cycle, and constructs a mechanism to evaluate a node's weight. An improved Raft consensus algorithm based on node weight is then proposed. Nodes with greater weights are more likely to become leading nodes, promoting active compliance and green consumption by nodes and reducing carbon emissions. A simulation shows that the improved Raft consensus mechanism enhances the reliability of leading nodes, improves the efficiency of the distributed power transaction, increases the generation of renewable energy, and encourages the consumption of new energy. [ABSTRACT FROM AUTHOR]

Currently researchers are intensely exploring the potential of polymer coated inorganic nanoparticles as materials of immense importance in context to theranostic applications, that implies a combination of diagnostic and therapeutic applications into a single tool. This enables early detection of a disease with the help of biomarkers, and treatment via improved biodistribution and targeted drug delivery in a kinetically controlled manner. Gold nanoparticles (AuNP) have often been the material of choice due to some specific advantages associated with them, e.g. ease of synthesis and surface functionalization, low toxicity and tunable optical properties. Surface grafting of the nanoparticles with polymers have been practiced widely in order to prevent their aggregation, forming stable core-shell nanostructures. Additionally, biofunctionalities like enzymes, peptides, nucleic acids, antibodies, etc have often been introduced for specific recognition of the diseased cells, followed by targeted release of the encapsulated drug. RAFT polymerization being one of the most versatile of controlled polymerization techniques, has been extensively used for surface grafting on the AuNPs to form polymer-AuNP nanohybrids systems. This review aims at highlighting some of the most interesting research works reported on RAFT synthesized polymer-grafted AuNP over the last decade and their potential usefulness in context to different biomedical applications. [ABSTRACT FROM AUTHOR]

Poly(glycerol monomethacrylate)-block-poly(2-hydroxypropyl methacrylate) (PGMA-PHPMA) with worm-like morphology is a typical example of reversible addition–fragmentation chain transfer (RAFT) dispersion polymerized thermo-responsive copolymer via polymerization-induced self-assembly (PISA) in aqueous solution. Chain transfer agents (CTAs) are the key component in controlling RAFT, the structures of which determine the end functional groups of the polymer chain. It is therefore of interest to monofunctionalize the polymers via CTA moiety, for bioactive functionality conjugation and in the meantime maintain the precisely controlled morphology of the copolymers and the related property. In this work, a newly designed CTA 5-(2-(tert-butoxycarbonylamino) ethylamino)-2-cyano-5-oxopentan-2-yl benzodithioate (t-Boc CPDB) was synthesized and used for the RAFT polymerization of PGMA45-PHPMA120. Subsequently, PGMA45-PHPMA120 copolymers with primary amine, maleimide, and reduced L-glutathione (a tripeptide) monofunctionalized terminals were synthesized via deprotection and conjugation reactions. These monofunctionalized copolymers maintain worm-like morphology and thermo-responsive property in aqueous solution (10% w/v), as confirmed by the transmission electron microscopy (TEM) images, and the observation of the phase transition behavior in between 4 °C and room temperature (~20 °C), respectively. Summarily, a range of thermo-responsive monofunctionalized PGMA45-PHPMA120 diblock copolymer worms were successfully synthesized, which are expected to offer potential biomedical applications, such as in polymer therapeutics, drug delivery, and diagnostics. [ABSTRACT FROM AUTHOR]

Herein, the poly(ɛ‐caprolactone)‐poly(ethylene glycol)‐poly(ɛ‐caprolactone) (PCL‐PEG‐PCL) macro xanthate reversible addition–fragmentation chain‐transfer agent is obtained on the polyethylene glycol (PEG) (600, 1000, and 1500 g mol−1) block, after the addition of ɛ‐caprolactone via ring‐opening polymerization. Then, poly (styrene‐b‐ɛ‐caprolactone‐b‐PEG‐b‐ɛ‐caprolactone‐b‐styrene) pentablock copolymer is synthesized reversible addition–fragmentation chain‐transfer (RAFT) solution polymerization technique via mediated PCL‐PEG‐PCL xanthate macro‐RAFT agents and 2,2′‐azobisisobutyronitrile as initiator. The products are demonstrated using Fourier transform infrared spectrophotometer (FT‐IR), proton nuclear magnetic resonance (1H‐NMR), carbon nuclear magnetic resonance (13C‐NMR), differential scanning calorimetry (DSC), and gel permeation chromatography (GPC) analyses. First‐order linear kinetic graphs of the reaction mechanism are observed with an increase in molecular weights (MW) between 16 000 and 36 000 g mol−1. The narrow dispersity (Đ = 1.40–1.48) polymer formation of styrene (St) controlled by RAFT polymerization confirms the increase in molecular weight according to the polymerization time. The reaction kinetics are first order and the rate constants are found to be k1 = 6.16 × 10−4s−1, k2 = 6.91 × 10−4 s−1 and k3 = 7.33 × 10−4 s−1. Thermal and spectroscopic analyses prove that the reactions are carried out successfully. [ABSTRACT FROM AUTHOR]

The stability of a structure could be achieved either by adopting strong foundation or by improving the strength of the soil. This study is an attempt to investigate the behavior of a raft foundation (U-RF) upon reinforcing with geogrid (RF-R-Gr) and reinforcing with geocell (RF-R-Gc). The results of the study showed that optimal depth for placement of geogrid was found to be 0.3B (B is width of raft) while optimal depth for geocell varied from 0.1B to 0.15B. It was also found that the Bearing Capacity Ratio (BCR) for RF-R-Gr was typically six times higher than U-RF, while for RF-R-Gc it was eleven times higher than U-RF. Further, the outcomes of experimental study were modeled using Artificial Neural Networks (ANN) to predict the settlements. It was found that ANN models predicted settlement with higher values of correlation coefficient (r) as 0.9996 for RF-R-Gr and 0.9995 for RF-R-G. [ABSTRACT FROM AUTHOR]

Based on the practical Byzantine fault tolerance algorithm (PBFT), a grouped multilayer PBFT consensus algorithm (GM-PBFT) is proposed to be applied to digital asset transactions in view of the problems with excessive communication complexity and low consensus efficiency found in the current consensus mechanism for digital asset transactions. Firstly, the transaction nodes are grouped by type, and each group can handle different types of consensus requests at the same time, which improves the consensus efficiency as well as the accuracy of digital asset transactions. Second, the group develops techniques like validation, auditing, and re-election to enhance Byzantine fault tolerance by thwarting malicious node attacks. This supervisory mechanism is implemented through the Raft consensus algorithm. Finally, the consensus is stratified for the nodes in the group, and the consensus nodes in the upper layer recursively send consensus requests to the lower layer until the consensus request reaches the end layer to ensure the consistency of the block ledger in the group. Based on the results of the experiment, the approach may significantly outperform the PBFT consensus algorithm when it comes to accuracy, efficiency, and preserving the security and reliability of transactions in large-scale network node digital transaction situations. [ABSTRACT FROM AUTHOR]

Previously, we established that as a function of its mode of interaction with its ligand or cellular conditions such as membrane lipids, preexisting signaling intermediates activation status, a transmembrane receptor, as represented here with CD40, can induce counteractive cellular responses. Using CD40-binding peptides, recombinant mutated CD40-ligands, and an agonistic antibody, we have established the functional duality of CD40. CD40 builds up two constitutionally different signalosomes on lipid raft and non-raft membrane domains initiating two different signaling pathways. Although this initial signaling may be modified by the pre-existing signaling conditions downstream and may be subjected to feed-forward or negative signaling effects, the initial CD40-CD40L interaction plays a crucial role in the functional outcome of CD40. Herein, we have reviewed the influence of interaction between the CD40-CD40L evoking the functional duality of CD40 contingent upon different physiological states of the cells. [ABSTRACT FROM AUTHOR]

Zwitterionic polymers are widely employed hydrophilic building blocks for antifouling coatings with numerous applications across a wide range of fields, including but not limited to biomedical science, drug delivery and nanotechnology. Zwitterionic polymers are considered as an attractive alternative to polyethylene glycol because of their biocompatibility and effectiveness to prevent formation of biofilms. To this end, zwitterionic polymers are classified in two categories, namely polybetaines and polyampholytes. Yet, despite a fundamental interest to drive the development of new antifouling materials, the chemical composition of zwitterionic polymer remains severely limited. Here, we show that poly(sulfur ylides) that belong to the largely overlooked class of poly(ylides), effectively prevent the formation of biofilms from pathogenic bacteria. While surface energy analysis reveals strong hydrogen‐bond acceptor capabilities of poly(sulfur ylide), membrane damage of pathogenic bacteria induced by poly(sulfur ylides) indicates toxicity towards bacteria while not affecting eucaryotic cells. Such synergistic effect of poly(sulfur ylides) offers distinct advantages over polyethylene glycol when designing new antifouling materials. We expect that our findings will pave the way for the development of a range of ylide‐based materials with antifouling properties that have yet to be explored, opening up new directions at the interface of chemistry, biology, and material science. [ABSTRACT FROM AUTHOR]

Ecuador is one of the main balsa wood marketers, thanks to its subtropical zone which presents optimal geographical and climatic conditions that benefit its development. The balsa, O. pyramidale (Cav. ex Lam.) Urb., is a species native to the American tropics; It is frequently found in disturbed and degraded areas. The objective of this research was to determine the effects of five substrates on the propagation of Ochroma pyramidale (Cav. ex Lam.) Urb. seedlings in the Paján canton, province of Manabí. The research was carried out in the field from September to December 2020 in the Paján canton on the "LA RAQUELITA" Farm owned by Mr. Euclides Plaza, located at Km. 4 via Colimes, between the Geographic Coordinates 80°25'12" of west longitude and 01°34'12" south latitude, an altitude of 200 meters above sea level. The ecological zone is a very dry tropical forest type (bmsT), characterized by an average daily temperature of 25 °C, receives average annual rainfall of 1626 mm, with a pH of 7, relative humidity 86% and 1146.6 hours of sunshine per day. anus. The treatments under study were T1 Black earth 100% (Control), T2 (Black earth 75%, sand 25%), T3 (Black earth 50%, sand 25%, humus 25%), T4 (Black earth, 33%, sand 33%, humus 33%) and T5 (black earth 50%, humus 50%), the results indicate that the substrate made up of black earth 50%, humus 50% allows for better results in the propagation of Ochroma pyramidale (Cav. ex Lam.) Urb. in nursery stage. [ABSTRACT FROM AUTHOR]