Encapsulation Mechanism Research Articles

Nanotechnology-Driven Delivery of Caffeine Using Ultradeformable Liposomes-Coated Hollow Mesoporous Silica Nanoparticles for Enhanced Follicular Delivery and Treatment of Androgenetic Alopecia

Androgenetic alopecia (AGA) is caused by the impact of dihydrotestosterone (DHT) on hair follicles, leading to progressive hair loss in men and women. In this study, we developed caffeine-loaded hollow mesoporous silica nanoparticles coated with ultradeformable liposomes (ULp-Caf@HMSNs) to enhance caffeine delivery to hair follicles. Caffeine, known to inhibit DHT formation, faces challenges in skin penetration due to its hydrophilic nature. We investigated caffeine encapsulated in liposomes, hollow mesoporous silica nanoparticles (HMSNs), and ultradeformable liposome-coated HMSNs to optimize drug delivery and release. For ultradeformable liposomes (ULs), the amount of polysorbate 20 and polysorbate 80 was varied. TEM images confirmed the mesoporous shell and hollow core structure of HMSNs, with a shell thickness of 25–35 nm and a hollow space of 80–100 nm. SEM and TEM analysis showed particle sizes ranging from 140–160 nm. Thermal stability tests showed that HMSNs coated with ULs exhibited a Td10 value of 325 °C and 70% residue ash, indicating good thermal stability. Caffeine release experiments indicated that the highest release occurred in caffeine-loaded HMSNs without a liposome coating. In contrast, systems incorporating ULp-Caf@HMSNs exhibited slower release rates, attributable to the dual encapsulation mechanism. Confocal laser scanning microscopy revealed that ULs-coated particles penetrated deeper into the skin than non-liposome particles. MTT assays confirmed the non-cytotoxicity of all HMSN concentrations to human follicle dermal papilla cells (HFDPCs). ULp-Caf@HMSNs promoted better cell viability than pure caffeine or caffeine-loaded HMSNs, highlighting enhanced biocompatibility without increased toxicity. Additionally, ULp-Caf@HMSNs effectively reduced ROS levels in DHT-damaged HFDPCs, suggesting they are promising alternatives to minoxidil for promoting hair follicle growth and reducing hair loss without increasing oxidative stress. This system shows promise for treating AGA.

Scabbard: An Exploratory Study on Hardware Aware Design Choices of Learning with Rounding-based Key Encapsulation Mechanisms

Recently, the construction of cryptographic schemes based on hard lattice problems has gained immense popularity. Apart from being quantum resistant, lattice-based cryptography allows a wide range of variations in the underlying hard problem. As cryptographic schemes can work in different environments under different operational constraints such as memory footprint, silicon area, efficiency, power requirement, and so on, such variations in the underlying hard problem are very useful for designers to construct different cryptographic schemes. In this work, we explore various design choices of lattice-based cryptography and their impact on performance in the real world. In particular, we propose a suite of key-encapsulation mechanisms based on the learning with rounding problem with a focus on improving different performance aspects of lattice-based cryptography. Our suite consists of three schemes. Our first scheme is Florete, which is designed for efficiency. The second scheme is Espada, which is aimed at improving parallelization, flexibility, and memory footprint. The last scheme is Sable, which can be considered an improved version in terms of key sizes and parameters of the Saber key-encapsulation mechanism, one of the finalists in the National Institute of Standards and Technology’s post-quantum standardization procedure. In this work, we have described our design rationale behind each scheme. Furthermore, to demonstrate the justification of our design decisions, we have provided software and hardware implementations. Our results show Florete is faster than most state-of-the-art KEMs on software platforms. For example, the key-generation algorithm of high-security version Florete outperforms the National Institute of Standards and Technology’s standard Kyber by 47%, the Federal Office for Information Security’s standard Frodo by 99%, and Saber by 57% on the ARM Cortex-M4 platform. Similarly, in hardware, Florete outperforms Frodo and NTRU Prime for all KEM operations. The scheme Espada requires less memory and area than the implementation of most state-of-the-art schemes. For example, the encapsulation algorithm of high-security version Espada uses 30% less stack memory than Kyber, 57% less stack memory than Frodo, and 67% less stack memory than Saber on the ARM Cortex-M4 platform. The implementations of Sable maintain a tradeoff between Florete and Espada regarding software performance and memory requirements. Sable outperforms Saber at least by 6% and Frodo by 99%. Through an efficient polynomial multiplier design, which exploits the small secret size, Sable outperforms most state-of-the-art KEMs, including Saber, Frodo, and NTRU Prime. The implementations of Sable that use number theoretic transform-based polynomial multiplication (SableNTT) surpass all the state-of-the-art schemes in performance, which are optimized for speed on the Cortext M4 platform. The performance benefit of SableNTT against Kyber lies in between 7-29%, 2-13% for Saber, and around 99% for Frodo.

Screening and inclusion of luteolin for β-cyclodextrin: molecular simulations and experiments

In this study, we first established a guest small molecule screening mechanism by molecular simulation, and then screened lignans from 10 polyphenolic compounds to identify the most suitable guest molecule for encapsulation with β-cyclodextrin (β-CD). Subsequently, the subject-guest interactions and encapsulation mechanisms of lignans with β-CD, 2-hydroxypropyl-cyclodextrin (HP-β-CD) and 2,6-dimethyl-cyclodextrin (DM-β-CD) were investigated using a combination of molecular simulation and experimental methods, respectively. Molecular simulations were performed to calculate the microstructural parameters, including solubility parameters, binding energies, and mean square displacements. The simulation results demonstrated that DM-β-CD exhibited the strongest interaction with luteolin and formed the most stable inclusion complex. The inclusion complexes of luteolin with the three cyclodextrins were prepared by freeze-drying method, and the formation of the inclusion complexes was demonstrated using infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and ultraviolet-visible spectroscopy (UV). Phase solubility studies confirmed the formation of 1:1 stoichiometric inclusion complexes of lignans with cyclodextrins. Furthermore, 2,2-diphenyl-1-pyridine hydrazine (DPPH) free radical scavenging experiments demonstrated that the inclusion complexes exhibited enhanced antioxidant capacity. In light of these findings, it can be concluded that among the three cyclodextrins, DM-β-CD was optimally encapsulated with luteolin.

Hollow silicalite-1 encapsulated nickel nanoparticles as highly stable catalysts in maleic anhydride hydrogenation

Anchoring active metal particles in zeolite cages can significantly improve catalytic stability. In this study, hollow silicalite-1 (HoS-1) encapsulated Ni nanoparticles catalyst (Ni@HoS-1) was prepared using the impregnation method and applied in MA hydrogenation. The encapsulation mechanism was explained as the zeolite wall restricting the evaporation of water in HoS-1, hence Ni particles would be spontaneously enriched within the zeolite cage after drying and calcination. Experiments revealed the specially designed structure effectively protected Ni particles from leaching, and after 5 cycles in liquid-phase batch reactions, the final MA conversion of Ni@HoS-1 is 40.8 % higher than that of Ni/S-1 (85.5 % vs 44.7 %). Moreover, the low acidity of Ni@HoS-1 also delayed the accumulation of carbon deposits, extending the continuous reaction lifespan from 128 h of Ni/S-1 to 188 h. These findings provided a new perspective for the controllable locating of active metal sites against the supports.

Investigation of the complete encapsulation process of the noble gases by cryptophanes.

Based on DFT calculations (ωB97XD/def2-SVP/SVPfit), the ability and mechanism of noble gas encapsulation by series of cryptophanes were investigated. The focus was set to study the influence of different functionalization groups placed at the "gates" of cryptophanes cavity entrance by which the energy criteria were chosen as a main indicator for selective encapsulation of noble gases. Chosen functionalization groups were CH3, OCH3, OH, NH2, and Cl, and the encapsulation process of these cryptophanes was compared to a cryptophane without any functionalization group on its outer rim. Those groups were selected based on their different chemical properties and based on their size which will subsequently put additional steric restrictions on the cavity entrance. Chosen functionalization groups, beside their steric influence on the energy barrier magnitude, influence also the gating process through its chemical nature by which they can put an additional stabilization on noble gases encapsulation transition states enhancing the encapsulation process. Objective of this study was clearly to get better insights on the influence of those functional groups on the whole encapsulation process of noble gases. Large-size noble gases (Xe and Rn) from all noble gases are best accommodated in the cavities of selected cryptophanes, on the other hand these noble gases require to pass the highest energy barrier through the gating process. From the series of investigated cryptophanes, the cryptophane with the OCH3 functionalization group has been identified as the one with the best capabilities to host investigated noble gases, but on the other side this cryptophane puts the highest energy criteria required for the previous gating process.

Unlocking Intracellular Protein Delivery by Harnessing Polymersomes Synthesized at Microliter Volumes using Photo-PISA.

Efficient delivery of therapeutic proteins and vaccine antigens to intracellular targets is challenging due to generally poor cell membrane permeation and endolysosomal entrapment causing degradation. Herein, these challenges are addressed by developing an oxygen-tolerant photoinitiated polymerization-induced self-assembly (Photo-PISA) process, allowing for the microliter-scale (10µL) synthesis of protein-loaded polymersomes directly in 1536-well plates. High-resolution techniques capable of analysis at a single particle level are employed to analyze protein encapsulation and release mechanisms. Using confocal microscopy and super-resolution stochastic optical reconstruction microscopy (STORM) imaging, their ability to deliver proteins into the cytosol following endosomal escape is subsequently visualized. Lastly, the adaptability of these polymersomes is exploited to encapsulate and deliver a prototype vaccine antigen, demonstrating its ability to activate antigen-presenting cells and support antigen cross-presentation for applications in subunit vaccines and cancer immunotherapy. This combination of ultralow volume synthesis and efficient intracellular delivery holds significant promise for unlocking the high throughput screening of a broad range of otherwise cost-prohibitive or early-stage therapeutic protein and vaccine antigen candidates that can be difficult to obtain in large quantities. The versatility of this platform for rapid screening of intracellular protein delivery can result in significant advancements across the fields of nanomedicine and biomedical engineering.

Scenarios for Optical Encryption Using Quantum Keys

Optical communications providing huge capacity and low latency remain vulnerable to a range of attacks. In consequence, encryption at the optical layer is needed to ensure secure data transmission. In our previous work, we proposed LightPath SECurity (LPSec), a secure cryptographic solution for optical transmission that leverages stream ciphers and Diffie–Hellman (DH) key exchange for high-speed optical encryption. Still, LPSec faces limitations related to key generation and key distribution. To address these limitations, in this paper, we rely on Quantum Random Number Generators (QRNG) and Quantum Key Distribution (QKD) networks. Specifically, we focus on three meaningful scenarios: In Scenario A, the two optical transponders (Tp) involved in the optical transmission are within the security perimeter of the QKD network. In Scenario B, only one Tp is within the QKD network, so keys are retrieved from a QRNG and distributed using LPSec. Finally, Scenario C extends Scenario B by employing Post-Quantum Cryptography (PQC) by implementing a Key Encapsulation Mechanism (KEM) to secure key exchanges. The scenarios are analyzed based on their security, efficiency, and applicability, demonstrating the potential of quantum-enhanced LPSec to provide secure, low-latency encryption for current optical communications. The experimental assessment, conducted on the Madrid Quantum Infrastructure, validates the feasibility of the proposed solutions.

The Perils of Limited Key Reuse: Adaptive and Parallel Mismatch Attacks with Post-processing Against Kyber

The Module Learning With Errors (MLWE)-based Key Encapsulation Mechanism (KEM) Kyber is NIST's new standard scheme for post-quantum encryption. As a building block, Kyber uses a Chosen Plaintext Attack (CPA)-secure Public Key Encryption (PKE) scheme, referred to as Kyber.CPAPKE. In this paper we study the robustness of Kyber.CPAPKE against key mismatch attacks. We demonstrate that Kyber's security levels can be compromised if having access to a few mismatch queries of Kyber.CPAPKE, by striking a balance between the parallelization level and the cost of lattice reduction for post-processing. This highlights the imperative need to strictly prohibit key reuse in Kyber.CPAPKE. We further propose an adaptive method to enhance parallel mismatch attacks, initially proposed by Shao et al. at AsiaCCS 2024, thereby significantly reducing query complexity. This method combines the adaptive attack with post-processing via lattice reduction to retrieve the final secret key entries. Our method proves its efficacy by reducing query complexity by 14.6 % for Kyber512 and 7.5 % for Kyber768/Kyber1024. Furthermore, this approach has the potential to improve multi-value Plaintext-Checking (PC) oracle-based side-channel attacks and fault-injection attacks against Kyber itself.

The influence of pulse cell wall structure and cellular protein matrix on the in vitro digestion kinetics of starch: A dual encapsulation mechanism

The intrinsic characteristics and extrinsic processing of whole-pulse food modulate the starch digestion rate and extent. This study investigated the dual encapsulation mechanism of cell wall structure and protein matrix on the in vitro digestion properties of intracellular starch, using an isolated whole-pulse food model of intact pea cotyledon cells subjected to alkaline buffer and enzymatic treatments. Results showed that intact cells with the maximum protein matrix content (18.9 %) exhibited the lowest peak temperature (71.4 °C, uncooked and 58.1 °C, cooked), enthalpy change (3.4 J/g, uncooked and 2.0 J/g, cooked), relative crystallinity (11.6 %), and starch digestion rate (0.0248 min−1) and extent (11.9 %) compared to alkaline buffer and enzymatic treatments. Even after enzymatic treatment, cells with minimal protein matrix content (1.8 %) exhibited a starch digestion rate (0.0387 min−1) and extent (39.7 %), which were still lower than those of isolated starch (0.0480 min−1 and 56.8 %). These findings indicate that the protein matrix and cell walls act as a dual encapsulation system to slow starch hydrolysis. This provides a theoretical basis and technical guidance for developing low-glycemic whole-pulse foods.

Hardware Acceleration for High-Volume Operations of CRYSTALS-Kyber and CRYSTALS-Dilithium

Many high-demand digital services need to perform several cryptographic operations, such as key exchange or security credentialing, in a concise amount of time. In turn, the security of some of these cryptographic schemes is threatened by advances in quantum computing, as quantum computer could break their security in the near future. Post-quantum cryptography (PQC) is an emerging field that studies cryptographic algorithms that resist such attacks. The National Institute of Standards and Technology (NIST) has selected the CRYSTALS-Kyber Key Encapsulation Mechanism and the CRYSTALS-Dilithium Digital Signature algorithm as primary PQC standards. In this article, we present field-programmable gate array (FPGA)-based hardware accelerators for high-volume operations of both schemes. We apply high-level synthesis (HLS) for hardware optimization, leveraging a batch processing approach to maximize the memory throughput and applying custom HLS logic to specific algorithmic components. Using reconfigurable FPGAs, we show that our hardware accelerators achieve speedups between 3 \(\times\) and 9 \(\times\) over software baseline implementations, even over ones leveraging CPU vector architectures. Furthermore, the methods used in this study can also be extended to the new CRYSTALS-based NIST FIPS drafts, ML-KEM and ML-DSA, with similar acceleration results.

Integrating strategy to investigate the formation and stabilization mechanisms of Curcumin-Cyclodextrin inclusion complexes: experimental characterizations and multi-scale computational simulations.

The Cyclodextrin (CD) encapsulation technology can significantly enhance the water solubility of Curcumin (CUR) and effectively protect it against chemical degradations. In the current study, a combination of experimental and multi-scale computational approaches was used to investigate the binding mechanism between CUR and β-CDs (β-CD, 2-HP-β-CD, Me-β-CD, and DM-β-CD). Phase solubility studies showed that β-CDs exhibited a strong binding affinity with CUR and significantly enhanced its solubility. SEM, PXRD, DSC, and TG analysis confirmed the formation of inclusion complexes, resulting in the transition of CUR from crystalline to an amorphous state. FTIR, 1H, and 13CNMR spectra deduced that CUR may have multiple binding conformations with β-CDs. The rationality of molecular dynamics simulation systems was confirmed by comparing the simulated IR spectrum from quantum mechanics with the experimental IR spectrum. MM-PBSA and umbrella sampling simulation calculated the binding free energy of the CUR/CD inclusion complexes, ranking Me-β-CD > DM-β-CD > 2-HP-β-CD > β-CD, and clarified that van der Waals interaction played a major role in stabilizing the inclusion complexes. RDF analysis confirmed that the release of high-energy water molecules drove the formation of the CUR/CD inclusion complex, and the β-CD substituents affected their exterior hydration layer. Additionally, principal component analysis (PCA) and non-covalent interaction analysis revealed three CUR/CD binding modes: bead-on-string, terminal insertion, and V-shaped-folding. The research strategy adopted here can serve as a paradigm for investigating the encapsulation mechanism of poorly soluble drugs with CDs.

Heightening polyoxometalate encapsulation efficiency for biaxial strain-induced catalytic activity boosting

Controllable assembly of polyoxometalates (POMs) in confined nanochannels is crucial to understand the host-guest structures and tailor the emerging properties for applications. Here, we report the encapsulation of polyoxometalates inside single-walled carbon nanotubes (SWNTs) for target catalytic regulation. Theoretical modeling predicts the confined polyoxomolybdates are able to induce biaxial tensile strains of SWNTs for more stable interaction with iron phthalocyanine (FePc) and tailor the charge distribution and coordination environment of targetable FeN4 sites, leading to improved catalytic activity toward oxygen reduction reaction (ORR). The polyoxomolybdates are confined in the SWNTs via redox-driven encapsulation mechanism with a POM encapsulation efficiency of about 21 %. The constructed FePc/SWNT@POM molecule catalyst exhibits a high half-wave potential of 0.90 V, excellent stability and methanol tolerance in alkaline medium. The zinc-air battery also presents prominent charge-discharge ability and long-term durability over 400 h with a peak power density of 190.8 mW cm–2.

Cyclodextrin grafted chitosan thermosensitive hydrogel using dual gelling agents: Drug delivery and antibacterial materials

In this paper, three kinds of cyclodextrin-grafted-chitosan (CD-g-CS) were synthesized from chitosan (CS) and β-cyclodextrin (β-CD) with different ratios. And a series of hydrogel with good temperature sensitivity and injectability were prepared by using sodium glycerophosphate (GP) and ammonium hydrogen phosphate (AHP) as dual gelling agents. The gelation formation time of hydrogel was short, and the shortest time was 0.75 min. The FTIR spectrum and 1H-NMR spectrum showed the structure of the compounds and intermolecular interactions. The molecular docking technique probed the encapsulation mechanism of the drug with β-CD. The SEM results showed that the hydrogel had a highly interconnected three-dimensional spatial structure. The swelling ratio of hydrogel was not less than 150 % within 1 h and the degradation rate of hydrogel was not less than 75 % within 14 days. The in vitro drug release results showed that the hydrogel had optimal sustained release effect, and the cumulative release ratio was 58.3 % in 34 h. The release kinetics analysis exhibited that the hydrogel conformed to the Riter-Peppas model. The hemocompatibility test and cytotoxicity test proved that the hydrogel had good biocompatibility and biosafety. The antibacterial experiments showed that the hydrogel could inhibit the biological activity of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Therefore, the CD-g-CS/GP-AHP hydrogel has a broad application prospect in the biological fields of drug delivery and antibacterial materials.

The analysis of Hermite factor of BKZ algorithm on small lattices

Lattice cryptography is one of the promising directions in modern cryptography research. Digital signatures and key encapsulation mechanisms on lattices have already been used in practice. In the future, such quantum-resistant transformations on lattices replace all standards that are not resistant to attacks on quantum computers. This makes the analysis of their security extremely relevant. Analysis of the security of cryptographic transformations on lattices is often reduced to the estimation of the minimum block size in the lattice reduction algorithm. For the expansion of small vectors, a reduction algorithm can be obtained for a given block size, the GSA model is often used, which uses the so-called Hermitian factor to predict the size of the vectors that the lattice reduction algorithm can obtain given the parameters. Asymptotic formulas have been developed to evaluate it in practice, but the question of their accuracy on cryptographic lattices has not been fully investigated. The work obtained estimates of the accuracy of the existing asymptotic estimates of the Hermite factor for lattices of sizes 120, 145, 170 for the classical BKZ algorithm. Research was conducted using the fpylll library. It was shown that the existing estimators are equivalent from a practical point of view and have a sufficiently small root mean square deviation from the true values. A formula was obtained that binds the root-mean-square error of approximation of the Hermit factor to the cryptographic parameters of lattices. The obtained results are useful for refining the security assessments of existing cryptographic transformations.

Preparation, Characterization and Sustained-release Study of Encapsulated Cinnamon Essential Oil Microcapsules

Aims: The aim of this study is to study preparation, characterization and sustained release of Encapsulated Cinnamon Essential Oil Microcapsules. Background: In this work, encapsulated cinnamon essential oil (CEO) microcapsules were prepared, characterized, and analyzed for their sustained-release properties. CEO microcapsules were encapsulated from an alginate polymer using homogenization and extrusion, and the encapsulation mechanism used was ionic gelation. The potent antibacterial properties of natural cinnamon oil extracts and their shelf-life activity can be reduced or eliminated as a result of deterioration caused by light, heat, and oxygen exposure during production. High-speed homogenization was utilized for the encapsulation, which encloses and protects the volatile compounds from degradation. Objective: The objective of this study is to synthesize sustained-release encapsulated cinnamon essential oil (CEO) microcapsules. Method: The preparation of encapsulated cinnamon oil was achieved through homogenization. The extrusion method was employed to obtain microcapsules encapsulating liquid active ingredients (AI) with alginate polymer to induce ionic gelation. Results: SEM and Optical images reveal that all microcapsules maintain their spherical shape with clearly defined membranes. XPS analysis indicates the presence of oxygen (O), carbon (C), and sodium (Na) on the surface, suggesting the presence of an alginate-based ionic gelation. Chromatographic studies demonstrate a high encapsulation efficiency of 99%. The average microcapsule size is 261.5 nm for the fresh sample and 278 nm after 3.5 months. The zeta potential is -29.8 mV for the fresh sample and -28.2 mV after 3.5 months. Notably, there is no evidence of microcapsule agglomeration during the 3.5-month storage period as observed in the study. TGA data reveals that only 7.5% of the adsorbed water and essential oil mixture is lost at 40°C over 4 hours, in contrast to 11.7% for the adsorbed water material, indicating a sustained release of the encapsulated CEO from the microcapsules. Conclusion: The microcapsules exhibited an impressive encapsulation efficiency of 99%, demonstrating stability over the 3.5-month investigation period and showcasing sustained-release properties.

Dimensionality reduction using neural networks for lattice-based cryptographic keys

Post Quantum Cryptography has received an increasing amount of active research. This has been made prominent by the ever-growing field of quantum computing which poses a formidable threat to the modern cybersecurity landscape. Recently, post quantum schemes have been standardized for adoption into existing security services and protocols. In comparison to contemporary cryptographic schemes, these approaches are lagging behind in terms of performance with regards to functional speed and package sizes. A study into the various applications of neural networks used in classical and post quantum cryptographic schemes has been explored to demonstrate their different possible applications within the various fields of cybersecurity. The main contribution of this work is to investigate the feasibility of dimensionality reduction using the autoencoder neural network on lattice-based keys generated by the Kyber key encapsulation mechanism scheme. Moreover, this work also presents a comparative analysis of the different implemented autoencoder models to showcase their relative performance.

Highly dispersed Ni nanoparticles confined in mesoporous SBA-15 for methane dry reforming with improved coke resistance and stability

Methane dry reforming (DRM) is a promising route for sustainable syngas production, in which Ni-based catalysts face challenges of metal sintering and coke formation. In this work, highly dispersed Ni nanoparticles (NPs) embedded in the mesopores of SBA-15 were prepared using a simple solid-state impregnation (SSI) method. TEM and cross-section HRTEM results clearly indicated that ultra-small Ni NPs (3–4 nm) were orderly dispersed within the mesopores of the SBA-15 support. Compared with the conventional wetness impregnation (WI) method, the Ni/SBA-15 catalyst prepared by solid-state impregnation method possessed much better catalytic activity, stability, and coke resistance in DRM. In-situ DRIFTS and semi-in-situ XRD were used to elucidate the dispersion and encapsulation mechanism of Ni within the mesopores of SBA-15 during the sample preparation process. Specifically, WI formed large NiO particles, while SSI formed smaller NiO NPs with stronger interaction between metal and support (SIMS) via forming Ni-O-Si species which is beneficial for the DRM reactivity. This work establishes relationships among catalyst preparation, structure, and DRM performance, paving the way for general template-assisted methods to prepare nanometallic catalysts for various applications.

Simulation on fabricating graphene-coated nickel powders through micromechanical exfoliation

Fabricating graphene-coated metal powders have become a crucial method for preparing advanced composites, yet the encapsulation mechanism and mechanical behavior remain unclear. In this work, the mechanical behavior of exfoliation, encapsulation as well as the uniform dispersion of graphene nanoplatelets (GNPs) was elucidated for the first time through molecular dynamics simulation based on a two-step three-dimensional (3D) vibration milling for fabricating graphene-coated nickel powders. The critical collision velocity for separating GNPs layer by layer was obtained and the geometric effects of bulk graphite on graphene exfoliation were analyzed. Compared to cuboid graphite, collisions between nickel powders and spherical graphite were prone to the exfoliation of few-layer graphene. A comprehensive experimental study was conducted to investigate the effects of geometry on the exfoliation of graphene. These results suggest that the cuboid graphite is prone to obtaining graphite sheets rather than few-layer graphene, leading to the formation of GSs/Ni composite powders. While the GNPs coated nickel powders are obtained after the two-step 3D vibration milling via spherical graphite. This study provides a comprehensive understanding of the preparation of graphene-coated nickel powders via micromechanical exfoliation.

Performance comparison of quantum-safe multivariate polynomial public key encapsulation algorithm

A novel quantum-safe key encapsulation algorithm, called Multivariate Polynomial Public Key (MPPK), was recently proposed by Kuang, Perepechaenko, and Barbeau. Security of the MPPK key encapsulation mechanism does not rely on the prime factorization or discrete logarithm problems. It builds upon the NP-completeness of the modular Diophantine equation problem, for which there are no known efficient classical or quantum algorithms. Hence, it is resistant to known quantum computing attacks. The private key of MPPK comprises a pair of multivariate polynomials. In a companion paper, we analyzed the performance of MPPK when these polynomials are quadratic. The analysis highlighted the MPPK high decapsulation time. We found that, while maintaining the security strength, the polynomials can be linear. Considerable performance gains are obtained for the decapsulation process. In this article, we benchmark the linear case and compare the results with the previous quadratic case.

Novel Copper Alginate Microspheres as Ecological Fungicides

Phytopathogenic fungi are living organisms that cause plant diseases and great damage to agricultural products. Despite the wide range of commercial fungicide products in use, there is a clear need for new and environmentally friendly fungicides. Here we propose a new ecological fungicide, copper alginate microspheres prepared by ionic gelation. The microspheres were characterized (morphology and topography, encapsulation efficiency, loading capacity, swelling behavior, rheology, kinetics and mechanism of copper ions release) and their in vitro antifungal potential against selected genera of phytopathogenic fungi was evaluated. Copper alginate microspheres inhibited spore germination of Botrytis cinerea. Compared to the control, the inhibition of B. cinerea spore germination (48%) was greater than that of the commercial fungicide Neoram® (22%). The mycelial growth of Cercospora beticola and Phytophthora ramorum was also significantly inhibited by the addition of copper alginate microspheres. Novel fungicide offer effective disease control while minimizing environmental impact and promoting sustainable agriculture practices.