Search Results (403)

Understanding the molecular mechanisms of protein–nanoparticle interactions is crucial for enabling the development of new applications in biomedicine and nanotechnology. Ubiquitin, an important and structurally small functional protein, plays a central role in numerous cellular processes. Therefore, in the current study, we focused on the few-layer graphene (FLG)–Ubiquitin complexes formed by exfoliating FLG structures using only water. Optical spectroscopic techniques (Raman, FT-IR, UV-Vis and circular dichroism) were employed to investigate these complexes on the molecular level. Overall, both CD and FT-IR data reveal that the formation of the FLG–Ubiquitin complexes occurred without inducing disordered structures in the protein. Based on the existence of a blue shift (hypsochromic shift) in the UV-Vis data, the presence of a single tyrosine and two phenylalanine residues in ubiquitin enables the detection of FLG-induced micro-environmental changes, particularly influencing the protein’s β-sheet and α-helix structures. The CD spectral results and CDPro quantitative estimations are in line with ATR FT-IR results, confirming the absence of disordered structure formation while altering the protein’s chirality. UV-Vis and CD spectroscopy results revealed concentration-dependent trends consistent with FLG–protein interactions that preserve the overall protein structure. This study has potential applications in both academic research and practical usage, particularly in biomedicine and nanotechnology specifically for FLG. Full article

Type-P5 ATPases are the least characterized among the P-type ATPases and this is especially true in the case of the malaria parasite. In this study, Spf1, a subtype-P5A ATPase of yeast, and ATP13A2, a subtype-P5B ATPase of humans, were used as templates to extensively characterize the sequences and structural features of haemosporidian type-P5 ATPases. Malaria parasites have both subtype-P5A and subtype-P5B ATPase genes and the structural features of the proteins recapitulate the known structures of subtype-P5A and subtype-P5B ATPases. Detailed structural analysis detected an additional α-helix in the P-domain of subtype-P5A ATPases, which is not found in subtype-P5B ATPases. This feature may be an additional signature to distinguish subtype-P5A and subtype-P5B ATPases, in addition to the previously described differences in the membrane loops of the N-terminal domain, the arm in the P-domain of subtype-P5A, and substrate differences. A notable difference in the type-P5 ATPases from the malaria parasite, as compared to the templates, is the insertion of multiple variable and low-complexity regions that form intrinsically disorganized loops. These loops may form a shroud-like structure that protects the core ATPase structure and/or participates in low-affinity interprotein interactions. Homology modeling did not provide definitive answers about the substrate specificity of the haemosporidian type-P5 ATPases. However, the haemosporidian subtype-P5A ATPase is likely an ER transmembrane dislocase as are the other subtype-P5A ATPases. In contrast, the subtype-P5B ATPases of the malaria parasite are not likely to be polyamine transporters in lysosomes, as have been described in fungi and metazoans. This suggests that subtype-P5B ATPases have undergone lineage-specific divergence in regard to their function(s). Full article

Vaccine adjuvants play a crucial role in the field of vaccinology, yet they remain one of the least developed and poorly characterized components of modern biomedical research. The limited availability of clinically approved adjuvants highlights the urgent need for new molecules with well-defined mechanisms and improved safety profiles. Hemocyanins, large copper-containing metalloglycoproteins found in mollusks, represent a unique class of natural immunomodulators. Hemocyanins serve as carrier proteins that help generate antibodies against peptides and hapten molecules. They also function as non-specific protein-based adjuvants (PBAs) in both experimental human and veterinary vaccines. Their mannose-rich N-glycans allow for multivalent binding to innate immune receptors, including C-type lectin receptors (e.g., MR, DC-SIGN) and Toll-like receptor 4 (TLR4), thereby activating both MyD88- and TRIF-dependent signaling pathways. Hemocyanins consistently favor Th1-skewed immune responses, which is a key characteristic of their adjuvant potential. Remarkably, their conformational stability supports slow intracellular degradation and facilitates dual routing through MHC-II and MHC-I pathways, thereby enhancing both CD4+ and CD8+ T-cell responses. Several hemocyanins are currently being utilized in biomedical research, including Keyhole limpet hemocyanin (KLH) from Megathura crenulata, along with those from other gastropods such as Concholepas concholepas (CCH), Fissurella latimarginata (FLH), Rapana venosa (RvH), and Helix pomatia (HpH), all of which display strong immunomodulatory properties, making them promising candidates as adjuvants for next-generation vaccines against infectious diseases and therapeutic immunotherapies for cancer. However, their structural complexity has posed challenges for their recombinant production, thus limiting their availability from natural sources. This reliance introduces variability, scalability issues, and challenges related to regulatory compliance. Future research should focus on defining the hemocyanin immunopeptidome and isolating minimal peptides that retain their adjuvant activity. Harnessing advances in structural biology, immunology, and machine learning will be critical in transforming hemocyanins into safe, reproducible, and versatile immunomodulators. This review highlights recent progress in understanding how hemocyanins modulate mammalian immunity through their unique structural features and highlights their potential implications as potent PBAs for vaccine development and other biomedical applications. By addressing the urgent need for novel immunostimulatory platforms, hemocyanins could significantly advance vaccine design and immunotherapy approaches. Full article

Collagen is a family of large, fibrous biomacromolecules common in animals, distinguished by unique molecular, structural, and functional properties. Despite the relatively low complexity of their sequences and the repetitive conformation of the triple helix, which is the defining feature of this family, unraveling sequence–stability and structure–function relationships in this group of proteins remains a challenging task. Considering the importance of the structural aspects in collagen chain recognition and selection, we reviewed our current knowledge of the heterotrimeric structures of non-collagenous (NC) regions that lack the triple helix sequence motif, Gly-X-Y, and are crucial for the correct folding of the functional states of these proteins. This study was conducted by simultaneously surveying the current literature, mining the structural database, and making predictions of the three-dimensional structure of these domains using highly reliable approaches based on machine learning techniques, such as AlphaFold. The combination of experimental structural data and predictive analyses offers some interesting clues about the structural features of heterotrimers formed by collagen NC regions. Structural studies carried out in the last decade show that for fibrillar collagens (types I, V, XI, and mixed V/XI), key factors include the formation of specific disulfide bridges and electrostatic interaction patterns. In the subgroup of collagens whose heterotrimers create supramolecular networks (types IV and VIII), available structural information provides a solid ground for the definition of the basis of the molecular and supramolecular organization. Very recent AlphaFold predictions and structural analyses of type VI collagen offer strong evidence of the specific domains in the NC region of the protein that are involved in chain selection and their staggering. Insightful crystallographic studies have also revealed some fundamental elements of the chain selection process in type IX collagen. Collectively, the data reported here indicate that, although some aspects (particularly the quantification of the relative contribution of the NC and triple helix regions to correct collagen folding) are yet to be fully understood, the available structural information provides a solid foundation for future studies aimed at precisely defining sequence–structure–function relationships in collagens. Full article

Block-based hybrid video coders typically use inter-prediction and bidirectionally coded (B) frames to improve compression efficiency. For this purpose, they employ look-ahead buffers, perform out-of-sequence frame coding, and implement similarity search-based general-purpose algorithms for motion estimation. While effective, these methods increase computational complexity and may not suit delay-sensitive practical applications such as real-time drone video transmission. If future motion can be predicted from external metadata, encoding can be optimized with lower complexity. In this study, a mathematical model for predicting motion vectors in drone video using only flight parameters is proposed. A remote-controlled drone with a fixed downward-facing camera recorded 4K video at 50 fps during autonomous flights over a marked terrain. Four flight parameters were varied independently, altitude, horizontal speed, vertical speed, and rotational rate. OpenCV was used to detect ground markers and compute motion vectors for temporal distances of 5 and 25 frames. Polynomial surface fitting was applied to derive motion models for translational, rotational, and elevational motion, which were later combined. The model was validated using complex motion scenarios (e.g., circular, ramp, helix), yielding worst-case prediction errors of approximately −1 ± 3 and −6 ± 14 pixels at 5 and 25 frames, respectively. The results suggest that flight-aware modeling enables accurate and low-complexity motion vector prediction for drone video coding. Full article

The basic Helix-Loop-Helix (bHLH) transcription factor family is crucial for plant growth, development, and stress response regulation. Despite previous studies on the bHLH gene family in Lagerstroemia indica, many bHLH genes remain unidentified, hindering further research on LibHLHs. Here, we identified 150 LibHLHs from the genome of L. indica and categorized them into 12 subfamilies (comprising 25 subgroups) showing conservation within subgroups. Cis-acting element analysis suggests roles in plant development, and responses to light, hormones, and stress. Examination of gene expression patterns highlighted the potential involvement of specific genes, such as LibHLH25 in subgroup IIIf, LibHLH68, LibHLH106, and LibHLH142 in subgroup IIIb, and LibHLH112 in subgroup VIIa, in anthocyanin biosynthesis in leaves of L. indica. This investigation enhances our comprehension of the complexity of the bHLH gene family and highlights the potential roles of LibHLHs in anthocyanin biosynthesis in L. indica, offering valuable insights for future genetic breeding endeavors. Full article

As a core component of high-speed trains, the traction drive system is also one of the main sources of both pass-by noise and interior noise. Current research primarily focuses on the modeling and design of its dynamic characteristics, while studies on its sound radiation remain relatively scarce. Existing investigations mainly rely on experimental and finite element methods. This paper proposes a rapid modeling method for the sound radiation of traction drive systems and analyzes the acoustic characteristics under different train speeds and gear helix angles. Taking an electric freight locomotive operating on China’s railways as the subject, the primary noise sources were identified through real-vehicle testing, thereby simplifying the non-dominant noise sources. By integrating a gear system dynamic model with theoretical models of gear meshing noise and motor noise, the proposed approach avoids the complexity and high computational cost associated with traditional finite element methods. The results show that at lower train speeds, the main noise source is the motor, while at higher speeds, it is the gearbox. As the train speed and helix angle increase, the radiated sound pressure of the traction drive system first increases and then decreases, though the sound field distribution and directivity remain largely unchanged. Full article

The root of Arnebia szechenyi Kanitz, known as “Mongolia Zicao,” has been widely used in traditional Chinese and Mongolia medicine. Herein, we aimed to characterize a pectin polysaccharide extracted from A. szechenyi Kanitz root (ASP), elucidate its structure, and evaluate potential immunomodulatory activities through in vitro assays. Sugar composition analysis and high-performance gel permeation chromatography (HPGPC) revealed that ASP is predominantly composed of GalA (45.44%), Gal (22.13%), and Ara (19.86%) with a homogenous molecular weight of 18.4 kD. ASP was identified as a typical pectin-like polysaccharide containing linear HG domains and potentially linked to complex branches with Ara and Glu residues. The monosaccharide analysis of the digestion product, D-ASP, supported this hypothesis. The Congo red test indicated the absence of a triple-helix structure in ASP and its digestion product D-ASP. ASP exhibited an irregular structure due to the branching fork, which disappeared after digestion, as observed by scanning electron microscopy. Additionally, ASP and D-ASP had certain antioxidant activities and significantly stimulated the release of cytokines (IL-1β, IL-6, TNF-a, NO), macrophage proliferation and phagocytic capability in RAW 264.7 cells in a dose-dependent manner. These findings outline the chemical and biological foundation for the development of novel drug candidates in the food and pharmaceutical industries. Full article

The WHO considers the Epidermal Growth Factor Receptor (EGFR) one of the key biomarkers of glioblastoma (GB). EGFR can be identified and targeted using molecular recognition elements (MoREs), like aptamers and aptamer–drug conjugates (ApDCs). Understanding the kinetics of anti-EGFR ApDC interactions with EGFR as well as the kinetics of their internalization into the cells is a crucial step for the further development of anti-EGFR ApDCs. For the first time, a novel approach was implemented to study real-time kinetics by measuring the cellular index (CI) using impedance (xCELLigence). Doxorubicin (DOX) was used as an indicator drug. Because DOX intercalates into the DNA double helix, aptamer–DOX non-covalent complexes were obtained. For the anti-EGFR DNA aptamer GR20, an additional duplex was constructed by synthesizing the extra region (GR20h) and via hybridization with the complementary oligonucleotide (h’) to form a duplex (hh’), thus creating the aptamer construct with complementary oligonucleotide (ACCO) GR20hh’. The original HPLC method quantified the assembly efficiency of an ACCO. The ACCO GR20hh’ retained affinity for the recombinant extracellular domain of EGFR, as measured using Biolayer Interferometry (BLI). According to cytofluorimetry, the ACCO GR20hh’ interacts with cells of continuous culture from GB patient (CCGBP) surgical samples. The DOX–ACCO GR20hh’ complexes are more efficiently internalized by EGFR+ cells lines A-431 and CCGBP 107 than DOX alone. Full article

Rice bran protein (RBP) is an important plant protein, but its functional properties are reduced due to the presence of disulfide bonds in the structure. Polyphenol modification is an effective strategy to improve protein functional properties. However, the interactions between quercetin (Que) and RBP have not been well-studied. In this study, we explored the mechanism of non-covalent interactions between RBP and Que and systematically evaluated the improvement of functional properties of the RBP–Que complex. The results revealed that the addition of Que can significantly affect the particle size, ζ-potential and protein flexibility of the RBP–Que complex, and the non-covalent interactions significantly altered the secondary structure (α-helix content decreased to 20.28%, β-sheet decreased to 22.02%, β-turn increased to 29.30% and random coil increased to 28.40%) and the tertiary conformation of RBP. Spectroscopic data showed that static quenching occurred. Thermodynamic parameters showed that ΔG, ΔH, and ΔS were negative, revealing that the binding process was spontaneous and exothermic and the main reactive bonds were the hydrogen bond and the van der Waals force. When the Que concentration was 120 μmol/g, the emulsifying and foaming properties were improved by 57.72% and 71.88% compared with the RBP, respectively. The study will expand the application of RBP in the food and beverage processing industry. Full article

In embedding systems, protein–polysaccharide complexes can be utilized as wall materials to improve the bioavailability and activity of bioactive substances during delivery. This study used the antisolvent precipitation method to manufacture gliadin from highland barley distillers’ grains (HBDGG)–chitosan (Cs) nanoparticles. Using a variety of characterization techniques, the microstructure and interaction mechanism of HBDGG-Cs nanoparticles were examined, and their stability was assessed. In comparison to HBDGG, the results indicated that the addition of Cs enhanced the intensity of UV absorption and reduced the intensity of fluorescence. The content of α-helix dropped, while β-sheet, β-turn, and irregularly coiled content rose in the complexes. Hydrogen bonding, hydrophobic interactions, and electrostatic interactions were the primary forces that formed the nanoparticles. The contact force between HBDGG and Cs enhanced the stability of the nanoparticles. The particle size, polydispersity index (PDI), and zeta potential were 526.10 ± 11.78 nm, 0.20 ± 0.06, and 51.31 ± 0.66 mV, respectively, at a mass ratio of 1:1 between HBDGG and Cs. The nanoparticles exhibited good ionic, acid-base, and storage stability in addition to being widely distributed. This work offers a theoretical foundation for employing HBDGG-Cs nanoparticles to deliver bioactive components in food as well as a novel method for the comprehensive usage of HBDGG and Cs. Full article

The manufacture of industrial parts using silicone molds is becoming more frequent due to their versatility, durability, and precision, particularly in the production of complex components. One specific application is the manufacture of gears, which play a fundamental role in high-performance mechanical systems, where geometric accuracy is essential. Gears produced from resins offer several advantages such as efficient tribological performance, load resistance, noise reduction, and non-magnetic properties. The main goal of this paper is to determine the main factors affecting the final quality of resin gears by analyzing two principal gear quality parameters: teeth profile (ff$\alpha$) and helix deviation (ff$\beta$). This work includes a global analysis of all contributing factors influencing the final quality of gears manufactured. One of the main conclusions obtained is that gear quality depends on a combination of factors, such as mold properties, choice of resin, the manufacturing process, and the quality of the original model. As a result, two regression equations have been developed, relating all influencing factors to the two gear quality parameters (ff$\alpha$ and ff$\beta$). Different response surfaces have been obtained, enabling the definition of the required quality level of the model to achieve reproductions with certain ff$\alpha$ and ff$\beta$ values suitable for the intended application conditions. Full article

ROSCI0135 Bârnova-Repedea Forest, covering 12,236.20 ha, is a relatively large Natura 2000 site from Romania, though not as large as other Natura 2000 sites. However, in terms of the number of invertebrate species of community importance, with 18 species present, Bârnova Forest ranks as the fourth richest site in Romania, with the following species: Helix pomatia, Cordulegaster heros, Coenagrion ornatum, Paracaloptenus caloptenoides, Carabus variolosus, Rhysodes sulcatus, Cucujus cinnaberinus, Rosalia alpina, Morimus funereus, Cerambyx cerdo, Lucanus cervus, Bolbelasmus unicornis, Osmoderma barnabita (eremita), Parnassius mnemosyne, Zerynthia polyxena, Euphydryas maturna, Lycaena dispar, and Euplagia quadripunctaria. Bârnova-Repedea Forest can be considered a true mosaic of habitats, providing favourable conditions for the existence of these rare Natura 2000 species. The threats to the site are complex and challenging to manage. Full article

To address the complex pile–soil interaction mechanisms in predicting the compressive bearing capacity of HSCM piles (Helix Stiffened Cement Mixing piles) in marine soft soil regions, this study proposes an intelligent prediction method based on a GA-BPNN (Genetic Algorithm-Optimized Back Propagation Neural Network). A high-quality database comprising 1243 data points was established through finite element numerical simulations. By integrating data preprocessing techniques and the GA-BPNN model, the study systematically investigated the influence of helical blade spacing H₁ and H₂, strength ratio C_ref/S_u, and diameter ratio D_sc/D_H on bearing capacity. The results demonstrate that the GA-BPNN model achieves a prediction accuracy of 99.07%, with a mean squared error (MSE) of 7.20 × 10⁻³ and a coefficient of determination R² of 0.990. SHAP value analysis reveals that the strength ratio and diameter ratio are the dominant factors, exhibiting nonlinear relationships with bearing capacity characterized by saturation effects and threshold-dependent behavior. Laboratory tests further confirm strong correlations between cement–soil strength C_ref, formed pile diameter D_sc, and bearing capacity. The findings indicate that the GA-BPNN model provides an efficient and accurate approach for predicting the bearing capacity of HSCM piles, offering a reliable basis for engineering parameter optimization. Full article

This study proposes a multi-objective optimization scheduling method for edible oil transportation in smart manufacturing, focusing on centralized control and addressing challenges such as complex pipelines and shared resource constraints. The method employs the A* and Dijkstra pathfinding algorithm to determine the shortest pipeline route for each task, and estimates pipeline resource usage to derive a node cost weight function. Additionally, the transport time is calculated using the Hagen–Poiseuille law by considering the viscosity coefficients of different oil types. To minimize both cost and time, task execution sequences are optimized based on a Pareto front approach. A 3D digital model of the pipeline system was developed using C#, SolidWorks Professional, and the Helix Toolkit V2.24.0 to simulate a realistic production environment. This model is integrated with a 3D visual human–machine interface(HMI) that displays the status of each task before execution and provides real-time scheduling adjustment and decision-making support. Experimental results show that the proposed method improves scheduling efficiency by over 43% across various scenarios, significantly enhancing overall pipeline transport performance. The proposed method is applicable to pipeline scheduling and transportation management in digital factories, contributing to improved operational efficiency and system integration. Full article