Formation Of Structure Research Articles

Magnetically induced asymmetry and fuel-propulsion of lipid vesicles containing Fe3O4 micromotors

Artificial micro/nanomotors possess the capability to navigate intricate environments in accordance with a premeditated blueprint. Hybrid-propelled micromotors may present an efficacious approach in addressing scientific research quandaries. In this context, ferric oxide magnetic nanoparticles (Fe3O4 MNPs) are chosen as catalysts to be encapsulated within lipid vesicles (LVs) due to their superior quality and cost-effectiveness. The external magnetic field induces the aggregation of Fe3O4 MNPs within the LVs, resulting in the formation of an asymmetrical structure that promotes the catalytic reaction of hydrogen peroxide, producing oxygen to propel the movement of Fe3O4@LVs micromotors. The magnetic-fuel dual drive enables the Fe3O4@LVs micromotor to move 1.3 times faster than the LVs alone. Additionally, the magnetic field offers the advantage of controlling the direction of motor movement and facilitating retrieval for practical applications. This dual drive micromotor exhibits exceptional stability and reusability in aqueous solutions, underscoring its immense potential for future applications.

Investigation on Effects and Properties of Concrete Structure after Exposed to Fire

Abstract: The integrity and strength of the materials used in reinforced concrete structures are highly influenced by their exposure environment. Exposing the building materials to high temperature changes their performance. The change in the performance is a result of the change in the material properties. When subjecting a building material to fire, the occurring damage depends on the severity of the fire in terms ofthe fire temperature and time of exposure. This study investigates the effects of fireexposure on the set of RC beams. Through controlled experiments, varyingtemperatures from 3000C to 7000C areapplied to RC beams, analyzing changes in compressive strength, spalling, andmicrostructure by using rebound hammer,UPV meter and applying two-point loading in UTM. Results indicate a significantreduction in compressive strength with increasing fire temperature, attributed to thermal degradation of cement paste and aggregate. Additionally, changes inmicrostructure, such as pore structure alterations and formation of cracks, are observed. Also, few of RC beams were strengthened using GFRP sheets as a U- shaped wrapping to entire beam and U- shaped wrapping at certain intervals. The strengthened specimens are again tested in UTM for two-point loading, the results of the tests showed the feasibility of rehabilitating RC beams exposed to fire using GFRP plates.U-shaped wrapping to entire beam showed the good performance

RABV induces biphasic actin cytoskeletal rearrangement through Rac1 activity modulation.

Rabies virus (RABV) is highly lethal and triggers severe neurological symptoms. The neuropathogenic mechanism remains poorly understood. Ras-related C3 botulinum toxin substrate 1 (Rac1) is a Rho-GTPase that is involved in actin remodeling and has been reported to be closely associated with neuronal dysfunction. In this study, by means of a combination of pharmacological inhibitors, small interfering RNA, and specific dominant-negatives, we characterize the crucial roles of dynamic actin and the regulatory function of Rac1 in RABV infection, dominantly in the viral entry phase. The data show that the RABV phosphoprotein interacts with Rac1. RABV phosphoprotein suppress Rac1 activity and impedes downstream Pak1-Limk1-Cofilin1 signaling, leading to the disruption of F-actin-based structure formation. In early viral infection, the EGFR-Rac1-signaling pathway undergoes a biphasic change, which is first upregulated and subsequently downregulated, corresponding to the RABV entry-induced remodeling pattern of F-actin. Taken together, our findings demonstrate for the first time the role played by the Rac1 signaling pathway in RABV infection and may provide a clue for an explanation for the etiology of rabies neurological pathogenesis.IMPORTANCEThough neuronal dysfunction is predominant in fatal rabies, the detailed mechanism by which rabies virus (RABV) infection causes neurological symptoms remains in question. The actin cytoskeleton is involved in numerous viruses infection and plays a crucial role in maintaining neurological function. The cytoskeletal disruption is closely associated with abnormal nervous symptoms and induces neurogenic diseases. In this study, we show that RABV infection led to the rearrangement of the cytoskeleton as well as the biphasic kinetics of the Rac1 signal transduction. These results help elucidate the mechanism that causes the aberrant neuronal processes by RABV infection and may shed light on therapeutic development aimed at ameliorating neurological disorders.

Biochemical properties of chromatin domains define genome compartmentalization.

Chromatin three-dimensional (3D) organization inside the cell nucleus determines the separation of euchromatin and heterochromatin domains. Their segregation results in the definition of active and inactive chromatin compartments, whereby the local concentration of associated proteins, RNA and DNA results in the formation of distinct subnuclear structures. Thus, chromatin domains spatially confined in a specific 3D nuclear compartment are expected to share similar epigenetic features and biochemical properties, in terms of accessibility and solubility. Based on this rationale, we developed the 4f-SAMMY-seq to map euchromatin and heterochromatin based on their accessibility and solubility, starting from as little as 10000 cells. Adopting a tailored bioinformatic data analysis approach we reconstruct also their 3D segregation in active and inactive chromatin compartments and sub-compartments, thus recapitulating the characteristic properties of distinct chromatin states. A key novelty of the new method is the capability to map both the linear segmentation of open and closed chromatin domains, as well as their compartmentalization in one single experiment.

Structural formation yield of GeV centers from implanted Ge in diamond

In order to study the structural formation yield of germanium-vacancy (GeV) centers from implanted Ge in diamond, we have investigated its lattice location by using the β − emission channeling technique from the radioactive isotope 75Ge (t 1/2 = 83 min) produced at the ISOLDE/CERN facility. 75Ge was introduced via recoil implantation following 30 keV ion implantation of the precursor isotope 75Ga (126 s) with fluences around 2 × 1012–5 × 1013 cm−2. While for room temperature implantation fractions around 20% were observed in split-vacancy configuration and 45% substitutional Ge, following implantation or annealing up to 900 °C, the split-vacancy fraction dropped to 6%–9% and the substitutional fraction reached 85%–96%. GeV complexes thus show a lower structural formation yield than other impurities, with substitutional Ge being the dominant configuration. Moreover, annealing or high-temperature implantation seem to favor the formation of substitutional Ge over GeV. Our results strongly suggest that GeV complexes are thermally unstable and transformed to substitutional Ge by capture of mobile carbon interstitials, which is likely to contribute to the difficulties in achieving high formation yields of these optically active centers.

Quantum barriers engineering toward radiative and stable perovskite photovoltaic devices

Efficient photovoltaic devices must be efficient light emitters to reach the thermodynamic efficiency limit. Here, we present a promising prospect of perovskite photovoltaics as bright emitters by harnessing the significant benefits of photon recycling, which can be practically achieved by suppressing interfacial quenching. We have achieved radiative and stable perovskite photovoltaic devices by the design of a multiple quantum well structure with long (∼3 nm) organic spacers with oleylammonium molecules at perovskite top interfaces. Our L-site exchange process (L: barrier molecule cation) enables the formation of stable interfacial structures with moderate conductivity despite the thick barriers. Compared to popular short (∼1 nm) Ls, our approach results in enhanced radiation efficiency through the recursive process of photon recycling. This leads to the realization of radiative perovskite photovoltaics with both high photovoltaic efficiency (in-lab 26.0%, certified to 25.2%) and electroluminescence quantum efficiency (19.7 % at peak, 17.8% at 1-sun equivalent condition). Furthermore, the stable crystallinity of oleylammonium-based quantum wells enables our devices to maintain high efficiencies for over 1000 h of operation and >2 years of storage.

Rheology and physical properties of sonicated chickpea concentrate with fructans in aqueous media and stable emulsions

Based on the rheological and other physical properties of chickpea concentrate (CPC)/fructan aqueous mixtures containing 0.2% carboxymethyl cellulose (CMC) and their respective emulsions, the macrostructure of the system was elucidated, and its effect on the stability of the proposed emulsions was evaluated. The zeta potential and particle size of the CPC dispersions subjected to ultrasonic treatment were analyzed. Neither agave (AGF) nor chicory fructans (CHF) affected the rheological behavior (Newtonian) of aqueous systems containing only CPC. A Carreau behavior was observed when CMC was added. A synergistic effect occurred when 6% CHF was mixed with CMC. Furthermore, CHF led to a higher overall viscosity than AGF in the systems studied. Fructans changed the total charge of the protein dispersion and increased the particle size. The viscoelastic properties confirmed the liquid-like behavior of the aqueous mixtures. Emulsions containing CPC/CMC mixtures and fructans exhibited thixotropic behavior; emulsions containing 30% oil followed the Carreau model, while emulsions containing 60% oil were fitted to the Hershel-Bulkley model for upward and downward shear rate curves. The latter behavior corresponded to the formation of a weak gel structure and a flocculated oil droplet network, as confirmed by the mechanical spectra. The droplet size in the emulsions decreased in the presence of fructans, particularly for 3% CHF and 6% AGF. However, 6% CHF led to the formation of the most kinetically stable emulsions. These results confirm the possibility of incorporating CPC and fructans as oil-in-water emulsions stabilized with CMC into healthy plant-based products.

Surface Encapsulation of Layered Oxide Cathode Material with NiTiO3 for Enhanced Cycling Stability of Na-Ion Batteries

Abstract In Na-ion batteries, O3-type layered oxide cathode materials encounter challenges such as particle cracking, oxygen loss, electrolyte side reactions, and multi-phase transitions during the charge/discharge process. This study focuses on surface coating with NiTiO3 achieved via secondary heat treatment using a coating precursor and the surface material. Through in-situ X-ray diffraction (XRD) and differential electrochemical mass spectrometry (DEMS), along with crystal structure characterizations of post-cycling materials, it was determined that the NiTiO3 coating layer facilitates the formation of a stable lattice structure, effectively inhibiting lattice oxygen loss and reducing side reaction with the electrolyte. This enhancement in cycling stability is evidenced by a capacity retention of approximately 74% over 300 cycles at 1C, marking a significant 30% improvement over the initial sample. Furthermore, notable advancements in rate performance were observed. Experimental results indicate that a stable and robust surface structure substantially enhances the overall stability of the bulk phase, presenting a novel approach for designing layered oxide cathodes with higher energy density.

Formation of Black Silicon in a Process of Plasma Etching with Passivation in a SF6/O2 Gas Mixture

This article discusses a method for forming black silicon using plasma etching at a sample temperature range from −20 °C to +20 °C in a mixture of oxygen and sulfur hexafluoride. The surface morphology of the resulting structures, the autocorrelation function of surface features, and reflectivity were studied depending on the process parameters—the composition of the plasma mixture, temperature and other discharge parameters (radical concentrations). The relationship between these parameters and the concentrations of oxygen and fluorine radicals in plasma is shown. A novel approach has been studied to reduce the reflectance using conformal bilayer dielectric coatings deposited by atomic layer deposition. The reflectivity of the resulting black silicon was studied in a wide spectral range from 400 to 900 nm. As a result of the research, technologies for creating black silicon on silicon wafers with a diameter of 200 mm have been proposed, and the structure formation process takes no more than 5 min. The resulting structures are an example of the self-formation of nanostructures due to anisotropic etching in a gas discharge plasma. This material has high mechanical, chemical and thermal stability and can be used as an antireflective coating, in structures requiring a developed surface—photovoltaics, supercapacitors, catalysts, and antibacterial surfaces.

Reduced Graphene-Oxide-Doped Elastic Biodegradable Polyurethane Fibers for Cardiomyocyte Maturation.

Conductive biomaterials offer promising solutions to enhance the maturity of cultured cardiomyocytes. While the conventional culture of cardiomyocytes on nonconductive materials leads to more immature characteristics, conductive microenvironments have the potential to support sarcomere development, gap junction formation, and beating of cardiomyocytes in vitro. In this study, we systematically investigated the behaviors of cardiomyocytes on aligned electrospun fibrous membranes composed of elastic and biodegradable polyurethane (PU) doped with varying concentrations of reduced graphene oxide (rGO). Compared to PU and PU-4%rGO membranes, the PU-10%rGO membrane exhibited the highest conductivity, approaching levels close to those of native heart tissue. The PU-rGO membranes retained anisotropic viscoelastic behavior similar to that of the porcine left ventricle and a superior tensile strength. Neonatal rat cardiomyocytes (NRCMs) and human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) on the PU-rGO membranes displayed enhanced maturation with cell alignment and enhanced sarcomere structure and gap junction formation with PU-10%rGO having the most improved sarcomere structure and CX-43 presence. hiPSC-CMs on the PU-rGO membranes exhibited a uniform and synchronous beating pattern compared with that on PU membranes. Overall, PU-10%rGO exhibited the best performance for cardiomyocyte maturation. The conductive PU-rGO membranes provide a promising matrix for in vitro cardiomyocyte culture with promoted cell maturation/functionality and the potential for cardiac disease treatment.

Computing edge version of metric dimension of certain chemical networks

In the modern digital sphere, graph theory is a significant field of research that has a great deal of significance. It finds widespread application in computer science, robotic directions, and chemistry. Additionally, graph theory is used in robot network localization, computer network problems and the formation of various chemical structures for networks. Moreover, it finds uses in exploring diffusion mechanisms and scheduling aircraft as well. The present research project examines and concentrates on the edge version of metric dimension of the Concealed Non-Kekuléan Benzenoid Hydrocarbon, Polythiophene, Backbone DNA network and Bakelite networks. All the mentioned networks have constant edge metric dimension except Bakelite network, as demonstrated by the results. If we talk about the applications of these networks, Polythiophene are used to treat prion disorders. It is also capable of detecting metal ions. The concept of Bakelite, which finds applications in the jewelry, electrical, cookware, sports, and clock industries, had an impact on the invention of modern polymers. The functions of DNA include information encoding, replication, mutation, and recombination gene expression.

Solvent-controlled structural variation of two Cd(II) compounds derived from thiophene dicarboxylate and 4-imidazol-1-yl-pyridine mixed ligands

Two solvent-controlled Cd(II) compounds, formulated as {[Cd2(Htdc)4(µ-imyp)(H2O)4]} (1), [Cd2(µ 2-tdc)2(µ-imyp)(DMF)2(H2O)2]n (2) (H2tdc= 2,5-thiophenedicarboxylic acid, imyp = 4-imidazol-1-yl-pyridine and DMF = N,N-dimethylformamide) have been synthesized by reactions of Cd(NO3)2·4H2O and H2tdc with imyp in different solvents, respectively. Both compounds were then characterized by single-crystal X-ray diffraction and other physicochemical methods. In 1, partially deprotonated Htdc− anion as terminal ligand and µ-imyp ligand connect Cd2+ ions to generate a discrete structure. In 2, completely deprotonated µ 2 – tdc2− anions and µ-imyp ligand link Cd2+ ions into a 1D double chain structure. Both compounds display 3D supramolecular structures through hydrogen bonding interactions. The results provided interesting insights into solvent effects on the structural formation of compounds 1 and 2. In addition, the solid-state photoluminescent properties of compounds 1 and 2 were also investigated. Two solvent-controlled Cd(II) compounds have been synthesized by reactions of Cd(NO3)2·4H2O and 2,5-thiophenedicarboxylic acid with 4-imidazol-1-yl-pyridine in the different solvents. One compound is a discrete structure, while the other compound has a 1D double chain structure. The results provided interesting insights into solvent effects on the structural formation of compounds.

Formation of Corrosion‐Resistant Nitride Coatings Based on Ti–Al–Cr–Fe–Ni High‐Entropy Alloy

The purpose of the work is to study the features of the phase and structure formation of coatings (Ti–Al–Cr–Fe–Ni)N formed by vacuum arc deposition and to study the influence of technological parameters of the deposition process on their corrosive properties. It is established that on the basis of the selected elements, it is possible to form a high‐entropy compound in the form of a solid solution. The structure of nitride coatings based on high‐entropy compounds formed by vacuum arc deposition is studied. It is established that the phase composition of coatings largely depends on the ratio of titanium and aluminum, which is determined by the technological parameters of deposition. An analysis of the results of the electrochemical behavior of coatings (Al,Ti,Fe,Cr,Ni)N shows that an increase in the corrosion resistance of these coatings is due to the synergistic effect of the formation of a solid substitution solution with a dense nanoscale structure and an increased relative aluminum content in them.

The Accurate Synthesis of a Multiscale Metallic Interface on Graphdiyne.

The accurate construction of composite material systems containing graphdiyne (GDY) and other metallic materials has promoted the formation of innovative structures and practical applications in the fields of energy, catalysis, optoelectronics, and biomedicine. To fulfill the practical requirements, the precise formation of multiscale interfaces over a wide range, from single atoms to nanostructures, plays an important role in the optimization of the structural design and properties. The intrinsic correlations between the structure, synthesis process, characteristic properties, and device performance are systematically investigated. This review outlines the current research achievements regarding the controlled formation of multiscale metallic interfaces on GDY. Synthetic strategies for interface regulation, as well as the correlation between the structure and performance, are presented. Furthermore, innovative research ideas for the design and synthesis of functional metal-based materials loaded onto GDY-based substances are also provided, demonstrating the promising application potential of GDY-based materials.

Controlling the physical properties of Ni1-xMnxFe2O4 multiferroic by the enhancement of ferroelectric phase through the increase of Mn content

The nanoparticles of the spinel ferrite system Ni1-xMnxFe2O4 with x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0 were prepared using the auto combustion flash method technique, by using the nitrates as cations source and urea as a fuel agent for combustion. The XRD pattern validates the formation of cubic spinel structure of Ni1-xMnxFe2O4 nanoparticles and traces of hematite phase. By increasing the annealing temperature, the lattice parameter and crystallite size were increased. At various frequencies, the dielectric properties and initial permeability were measured as a function of temperature. The DC resistivity was found to have a linear relationship with temperature, with two regions and one break point at Curie temperature (TC). SEM and TEM analyses are used to investigate the morphology of the samples, as well as the size and shape of the crystallites. The samples' morphology revealed the formation of a uniform and spherical structural distribution. The material transfer to multiferroic at high Mn content accordingly the ferroelectric and ferrimagnetic properties appear, which give the ability of the material to become magnetoelectric material.

9-fold symmetry is not essential for centriole elongation and formation of new centriole-like structures

As daughter centrioles assemble during G2, they recruit conserved Ana3/RTTN followed by its partner Rcd4/PPP1R35. Together, this contributes to the subsequent recruitment of Ana1/CEP295, required for the centriole’s conversion to a centrosome. Here, we show that Rcd4/PPP1R35 is also required to maintain 9-fold centriole symmetry in the Drosophila male germline; its absence causes microtubule triplets to disperse into a reduced number of doublet or singlet microtubules. rcd4-null mutant spermatocytes display skinny centrioles that elongate normally and localize centriolar components correctly. Mutant spermatocytes also have centrioles of normal girth that splay at their proximal ends when induced to elongate by Ana1 overexpression. Skinny and splayed spermatid centrioles can still recruit a proximal centriole-like (PCL) structure marking a capability to initiate features of centriole duplication in developing sperm. Thus, stable 9-fold symmetry of microtubule triplets is not essential for centriole growth, correct longitudinal association of centriole components, and aspects of centriole duplication.

Artificial Spores as Multi‐Functional Biocatalysts to Perform Biosynthetic Cascades

AbstractCells exhibit diverse structural formations such as biofilms and spores, enabling them to acquire novel functionalities. Many of these structures display biomacromolecules, including enzymes, tethered to cell walls to support various extracellular processes. Alternatively, encapsulating single cells with polymer coatings offers a strategy that circumvents the need for genetic engineering while imparting artificial functionalities to cells. Here, a universal method is presented for encapsulating single gram‐negative microbes with polymeric coatings based on the ancestral gall ink formed by tannic acid‐iron complexes. As a result, synthetic spores are achieved that selectively bind His‐tagged enzymes through the formation of unprecedented galloyl/imidazole‐Fe2+ complexes via ligand substitution demonstrated by density functional theory. These synthetic spores with a thickness of 41.5 ± 4.2 nm and a stiffness of 6.0 ± 3.5 GPa serve as biocatalytic materials for the one‐pot oxidative amination of diols into amino alcohols, facilitated by the cooperative catalysis between intracellular endogenous or recombinant oxidoreductases, and an extracellular transaminase from Pseudomonas fluorescens displayed at the spore surface. These spores maintain their performance in three consecutive batch cycles. Integrating isolated enzymes onto the surface of engineered microbes coated with polymers offers novel opportunities for synthetic biology, advancing the efficiency of biosynthetic cascades in solid‐state environments.

Comprehensive analysis of the complete mitochondrial genome of Lilium tsingtauense reveals a novel multichromosome structure.

Lilium tsingtauense mitogenome comprises 27 independent chromosome molecules, it undergoes frequent genomic recombination, and the rate of recombination and mutation between different repetitive sequences affects the formation of multichromosomal structures. Given the extremely large genome of Lily, which likely harbors additional genetic resources, it serves as an ideal material for studying the phylogenetic evolution of organisms. Although the Lilium chloroplast genome has been documented, the sequence of its mitochondrial genome (mitogenome) remains uncharted. Using BGI short reads and Nanopore long reads, we sequenced, assembled, and annotated the mitogenome of Lilium tsingtauense. This effort culminated in the characterization of Lilium's first complete mitogenome. Comparative analysis with other angiosperms revealed the unique multichromosomal structure of the L. tsingtauense mitogenome, spanning 1,125,108 bp and comprising 27 independent circular chromosomes. It contains 36 protein-coding genes, 12 tRNA genes, and 3 rRNA genes, with a GC content of 44.90%. Notably, three chromosomes in the L. tsingtauense mitogenome lack identifiable genes, hinting at the potential existence of novel genes and noncoding elements. The high degree of observed genome fragmentation implies frequent reorganization, with recombination and mutation rates among diverse repetitive sequences likely driving the formation of multichromosomal structures. Our comprehensive analysis, covering genome size, coding genes, structure, RNA editing, repetitive sequences, and sequence migration, sheds light on the evolutionary and molecular biology of multichromosomal mitochondria in Lilium. This high-quality mitogenome of L. tsingtauense not only enriches our understanding of multichromosomal mitogenomes but also establishes a solid foundation for future genome breeding and germplasm innovation in Lilium.

Regional variability of the Black Sea ichthyoplankton state during the change of the spring hydrological season to the summer

The species diversity and spatial distribution of ichthyoplankton in the coastal and open waters of the northern part of the Black Sea and the southwestern part of the Sea of Azov in June 2020 are presented. The species diversity and abundance of ichthyoplankton changed in accordance with the regional conditions of warming of the sea upper layer during the formation of a vertical thermal structure of the summer type. The most favorable conditions for the survival of ichthyoplankton were observed in the open and coastal waters of the Western Sector of research in the initial phase of the summer hydrological season.

First-principles screening of XSbF3 (X = Ba and Ra) fluoroperovskites: an insight into structural, optoelectronic and thermal properties

This work presents a computational study of the physical properties such as structural, electronic, optical and thermal properties of XSbF3 (X = Ba and Ra) fluoroperovskites. The calculations were performed using the density functional theory (DFT) calculations in conjunction with Quantum Espresso code. The stability of the crystal structure XSbF3 compounds is determined by binding energy (Eb) computations. The Eb values for BaSbF3 and RaSbF3 compounds are −19.25 and −20.04eV respectively, indicating that both studied compounds are stable. The optimized lattice constants for BaSbF3 and RaSbF3 compounds are 5.03 and 5.06 Å, respectively. The evaluation of electronic properties is conducted by electronic band structure, total density of states (DOS), and partial density of states (PDOS). It is observed from the PDOS plots that the p-states of Sb and F whereas the d-states of X atoms have the major contribution in the formation of the band structure. Various optical properties have been computed and compared. The static value of ε10 highlights the metallic nature of the studied compounds while RaSbF3 stands out for having the highest recorded value of ε20. The maximum nω values for BaSbF3 and RaSbF3 are 8.46 and 6.86 respectively indicating their potential for photoelectric applications. Furthermore when examining the properties it is evident that the BaSbF3 compound stands out as a material for energy storage because of its higher electron energy at 2.36 KJ/N.mol and lower electron free energy of −2.55 KJ/N.mol compared to the RaSbF3 compound. On the other hand, the RaSbF3 compound is an efficient material for catalysis due to its high ability to absorb heat energy from the external source, as compared to the BaSbF3 compound. This study is the first computational investigation of XSbF3 (X is Ba and Ra) compounds, which provides valuable insights into the physical properties of sb-based fluroperovskites and their potential applications.