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This study focuses on how soil's inherent variability, driven by environmental changes, introduces substantial uncertainty into geotechnical considerations. Voids forming underground are a key source of this uncertainty, affecting subsoil structures like piles. Using a two-dimensional discrete-element method and considering both fundamental (micro) and engineering (macro) approaches, this study investigates the influence of voids in sandy soil on a pile's behavior, especially on the pile's bearing capacity and lateral pressure coefficient acting upon its shaft. The results reveal a critical zone around the pile where voids can dramatically reduce the pile's bearing capacity, with load reductions of up to 63% in the most extreme cases. Surprisingly, voids have a minimal impact on the lateral pressure coefficient along the pile wall. Thus, it is deduced that the primary cause of the pile's load reduction in the presence of the void is the decreased resistance at the pile's tip. In summary, this research underscores how voids in sandy soil significantly affect the bearing capacity of piles, emphasizing the importance of understanding these effects for safe and efficient subsoil structure design in geotechnical engineering. [ABSTRACT FROM AUTHOR]

Jamu is an Indonesian traditional herbal medicine that has been practiced for generations. Jamu is made from various medicinal plants. Each plant has several compounds directly related to the target protein that are directly associated with a disease. A pharmacological graph can form relationships between plants, compounds, and target proteins. Research related to the prediction of Jamu formulas for some diseases has been carried out, but there are problems in finding combinations or compositions of Jamu formulas because of the increase in search space size. Some studies adopted the drug–target interaction (DTI) implemented using machine learning or deep learning to predict the DTI for discovering the Jamu formula. However, this approach raises important issues, such as imbalanced and high-dimensional dataset, overfitting, and the need for more procedures to trace compounds to their plants. This study proposes an alternative approach by implementing bipartite graph search optimization using the branch and bound algorithm to discover the combination or composition of Jamu formulas by optimizing the search on a plant–protein bipartite graph. The branch and bound technique is implemented using the search strategy of breadth first search (BrFS), Depth First Search, and Best First Search. To show the performance of the proposed method, we compared our method with a complete search algorithm, searching all nodes in the tree without pruning. In this study, we specialize in applying the proposed method to search for the Jamu formula for type II diabetes mellitus (T2DM). The result shows that the bipartite graph search with the branch and bound algorithm reduces computation time up to 40 times faster than the complete search strategy to search for a composition of plants. The binary branching strategy is the best choice, whereas the BrFS strategy is the best option in this research. In addition, the the proposed method can suggest the composition of one to four plants for the T2DM Jamu formula. For a combination of four plants, we obtain Angelica Sinensis, Citrus aurantium, Glycyrrhiza uralensis, and Mangifera indica. This approach is expected to be an alternative way to discover the Jamu formula more accurately.

Mineralized, bio-inspired nanofibrous scaffolds with controllable architecture and capable of mimicking essential characteristics of bone extracellular matrix at the micro- and nanoscale offer a promising strategy to restore functions or elicit favorable responses for bone tissue regeneration and repair. In this study, a simple approach to fabricate a hybrid scaffold with porous fibers for bone tissue engineering is presented. Non-woven multifunctional nano- and microfibers were fabricated using a block copolymer of poly(ε-caprolactone) (PCL) and poly(lactic acid) (PLA) (PL-b-CL) as a matrix and hydroxyapatite (HA) as a functional agent, dissolved in a binary solvent mixture. Physicochemical and thermal characterization as well as biocompatibility analyses were carried out using SaOS-2 cells. The results showed fibers with highly porous surfaces whose pore diameters range in the nanometer scale and all scaffolds exhibited hydrophobicity. HA-modified scaffolds significantly improved cell metabolic activity and proliferation as compared to pristine scaffolds. The biodegradable and biocompatible scaffolds proposed in this study carry great potential for various biomedical applications and in the future, it is expected that they can be used for controlled drug delivery by incorporating growth factors, proteins, or drugs to reduce the inflammatory response and/or to promote bone repair. [ABSTRACT FROM AUTHOR]

Fabrication and characterization of hybrid nanomats containing quantum dots can play a prominent role in the development of advanced biosensors and bio-based semiconductors. Owing to their size-dependent properties and controlled nanostructures, quantum dots (QDs) exhibit distinct optical and electronic characteristics. However, QDs include heavy metals and often require stabilizing agents which are toxic for biological applications. Here, to mitigate the use of toxic ligands, cadmium selenide quantum dots (CdSe QDs) were synthesized in situ with polyvinylpyrrolidone (PVP) at room temperature. The addition of PVP polymer provided size regulation, stability, and control over size distribution of CdSe QDs. The characterization of the optical properties of the CdSe QDs was performed using fluorescence and ultraviolet–visible (UV-Vis) spectroscopy. CdSe QDs exhibited a typical absorbance peak at 280 nm and a photoluminescence emission peak at 580 nm. Transmission electron microscopy (TEM) micrographs demonstrated that CdSe QDs having an average size of 6 ± 4 nm were obtained via wet chemistry method. CdSe QDs were immobilized in a blend of PVP and poly(L-lactide-co-ε-caprolactone) (PL-b-CL) copolymer that was electrospun to produce nanofibers. Scanning electron microscopy (SEM), thermal analyses and attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) were used to characterize properties of fabricated nanofibers. Both pristine and hybrid nanofibers possessed cylindrical geometry and rough surface features, facilitating increased surface area. Infrared absorption spectra showed a slight shift in absorbance peaks due to interaction of PVP-coated CdSe QDs and nanofiber matrix. The presence of CdSe QDs influenced the fiber diameter and their thermal stability. Further, in vitro biological analyses of hybrid nanofibers showed promising antibacterial effect and decline in cancer cell viability. This study offers a simple approach to obtain hybrid nanomats immobilized with size-controlled PVP-coated CdSe QDs, which have potential applications as biosensors and antibacterial and anticancer cell agents. [ABSTRACT FROM AUTHOR]

Periodic hybrid nanostructured materials based on aligned inorganic nanoparticles within self‐assembled copolymer matrixes aimed to harness the collective properties of generated functional nanomaterials. The nanoparticles are desirable for their useful magnetic, optical, catalytic, and electronic properties owed to the quantum confinement effect. For instance, gold, palladium and platinum as nanoparticles, have shown significant change in the physiochemical properties in comparison to their bulk materials. If the nanoparticles are aligned into well‐defined macroscopic periodic nanostructures in diverse of morphologies, the unique collective properties are significantly enhanced. These unique properties can be transformed to improve the performance of storage media, multi‐contact tracks solar panels and optoelectronic devices. Within this review, the nanofabrication tools will be presented as an alternative route to conventional top‐down methods for the fabrication of periodic nanostructured hybrid materials. A simple approach is reviewed to fabricate periodic nanostructured hybrid systems based on the directed assembly of inorganic nanoparticles into well‐defined periodic three‐dimensional nanostructures provided by the self‐assembling ability of block copolymers. The fabrications of varieties morphologies and the formation mechanism at different dimensions will be discussed as well as the characterization techniques. Finally, several applications of the proposed hybrid nanostructures are highlighted for the next generation of miniaturized devices. [ABSTRACT FROM AUTHOR]

Electrospun hybrid nanofibers, based on functional agents immobilized in polymeric matrix, possess a unique combination of collective properties. These are beneficial for a wide range of applications, which include theranostics, filtration, catalysis, and tissue engineering, among others. The combination of functional agents in a nanofiber matrix offer accessibility to multifunctional nanocompartments with significantly improved mechanical, electrical, and chemical properties, along with better biocompatibility and biodegradability. This review summarizes recent work performed for the fabrication, characterization, and optimization of different hybrid nanofibers containing varieties of functional agents, such as laser ablated inorganic nanoparticles (NPs), which include, for instance, gold nanoparticles (Au NPs) and titanium nitride nanoparticles (TiNPs), perovskites, drugs, growth factors, and smart, inorganic polymers. Biocompatible and biodegradable polymers such as chitosan, cellulose, and polycaprolactone are very promising macromolecules as a nanofiber matrix for immobilizing such functional agents. The assimilation of such polymeric matrices with functional agents that possess wide varieties of characteristics require a modified approach towards electrospinning techniques such as coelectrospinning and template spinning. Additional focus within this review is devoted to the state of the art for the implementations of these approaches as viable options for the achievement of multifunctional hybrid nanofibers. Finally, recent advances and challenges, in particular, mass fabrication and prospects of hybrid nanofibers for tissue engineering and biomedical applications have been summarized. [ABSTRACT FROM AUTHOR]

Template smart inorganic polymers within an organic polymeric matrix to form hybrid nanostructured materials are a unique approach to induce novel multifunctionality. In particular, the fabrication of one‐dimensional materials via electrospinning is an advanced tool, which has gained success in fulfilling the purpose to fabricate two‐dimensional nanostructured materials. We have explored the formation of novel hybrid nanofibers by co‐spinning of poly(ferrocenylphosphinoboranes) Fe A [{Fe(C5H5)(C5H4CH2PHBH2)}n] and Fe B [{Fe(C5H5)(C5H4PHBH2)}n] with poly(ethylene oxide) (PEO) and polystyrene (PS). Fe A and Fe B contain main‐group elements and a ferrocene moiety as pendent group and have different properties compared to their only carbon‐containing counterparts. The use of PEO and polystyrene provided a matrix to spin those inorganic polymers as hybrid nanofibers which were collected in the form of a nonwoven mat. They were characterized by multinuclear NMR spectroscopy, scanning electron microscopy (SEM), and IR spectroscopy. Thermal properties of the polymers have been checked by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). 1H, 31P, and 11B NMR and IR spectroscopy revealed the nature and types of interactions of the components after co‐spinning. The SEM micrographs identify the underlying unidirectional morphology of the generated hybrid nanofibers. Nonetheless, the DSC and TGA confirmed the significant boost toward the thermal stability of the resultant multifunctional fibers. It is believed that these unique types of multifunctional electrospun nanofibers will open new avenues toward the next generation of miniaturized devices. [ABSTRACT FROM AUTHOR]

Featured Application: Indolicidin-coated silver nanoparticles could be used as platforms in the dental field as oral disease preventive drug. Furthermore, nanomaterials could prevent oral cancers and balance oral health care. (1) Background: In dentistry, silver nanoparticles (AgNPs) have progressively earned great interest as antimicrobial drugs and are widely used in several biomedical fields. Recent progress in the analysis of complex bacterial communities has demonstrated the richness of the oral microbiota and the presence of numerous previously unexplained strains. Several efforts have been dedicated to the investigation of antimicrobial peptides (AMPs). Those peptides are a widespread group of small peptides against invading microbes. We report the production of a hybrid molecule composed of AgNPs and indolicidin, a well-known antibacterial peptide. (2) Methods: Spectroscopy and microscopy were used to analyze the optical features and to determine the size of the generated AgNPs. The AgNP antibacterial activity was evaluated versus oral Gram-positive and Gram-negative bacteria. (3) Results: The coated nanoparticles' antibacterial activity strongly inhibited the growth of microorganisms, with very low minimum inhibitory concentration (MIC) values in the range of 5–12.5 μg/mL. We hypothesize that this effect depended on the specific characteristics of the metal surface coated with indolicidin. The second result was that the coated nanoparticles observed cellular toxicity, was lower with respect to the toxicity of peptide and the naked AgNPs when used individually. (4) New investigations regarding antimicrobial effect of AgNPs coated with AMPs in oral infections are an urgent task. [ABSTRACT FROM AUTHOR]

ABSTRACT Dendritic-linear-dendritic (DLD) hybrids are highly functional materials combining the properties of linear and dendritic polymers. Attempts to electrospin DLD polymers composed of hyperbranched dendritic blocks of 2,2-bis(hydroxymethyl) propionic acid on a linear poly(ethylene glycol) core proved unsuccessful. Nevertheless, when these DLD hybrids were blended with an array of different biodegradable polymers as entanglement enhancers, nanofibrous nonwovens were successfully prepared by electrospinning. The pseudogeneration degree of the DLDs, the nature of the co-electrospun polymer and the solvent systems used for the preparation of the electrospinning solutions exerted a significant effect on the diameter and morphology of the electrospun fibers. It is worth-noting that aqueous solutions of the DLD polymers and only 1% (w/v) poly(ethylene oxide) resulted in the production of smoother and thinner nanofibers. Such dendritic nanofibrous scaffolds can be promising materials for biomedical applications due to their biocompatibility, biodegradability, multifunctionality, and advanced structural architecture. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45949. [ABSTRACT FROM AUTHOR]

A study is conducted to develop elastin-like-polymer [(VPGVG)(sub 2)(VPGEG)(VPGVG)(sub 2)](sub 15) and (VPGVG)(sub 48). This is based on a model (VPGVG) pentapeptide of the elastin, in which the second valine is replaced by an L-glutamic acid (E) in one pentapeptide out of five.

A coating system for polyester fabrics is developed containing metal effect pigments and a polyurethane binder. The metal pigment is made of copper, is of microscaled size and anisotropic shape. It is originally used for optical modification but can also be used to introduce other functional properties. The polyurethane binder is needed to fix the pigments on the textile surface. The aim of the current investigation is to present that the binder has not only the task to fix the pigment but can be also used to structure the pigment surface. The binder application leads to formation of microstructures on top of the pigment surface, probably as a result of a dewetting process. Based on this microstructured pigment surface, in future, textile coatings for improvement of water-repellent, antimicrobial, and antistatic properties could be developed. [ABSTRACT FROM AUTHOR]

Nanofabrication via self-assembled hybrid building blocks into well-defined structures is a powerful tool for engineering functional materials with designed properties. This review demonstrates different concepts for fabrication of one-dimensional (1D) nanostructures based on hybrid materials via directed self-assembly. The concepts describe how different types of self-assembled organic phases drive the unidirectional assembly of the inorganic moieties. The organic matrices are used to control the size and size distribution of the generated inorganic nanoparticles. Formation of the 1D structures is dependent on many parameters, such as nature of chemical composition of the hybrid organic–inorganic materials, the pH of the wet chemistry medium and the types of interactions at the interface that drive the structure formation. The collective properties of the designed 1D structures are induced by means of the degree of anisotropy and the alignment of different types of inorganic nanoparticles within the organic matrices. This cost-effective approach could potentially be extended to fabricate varieties of hybrid low dimensional nanostructures possessing unique collective electronic and optical properties, leading to a wide range of applications such as catalysis, bionanotechnology, nanoelectronics, photonics and optoelectronics. [ABSTRACT FROM AUTHOR]

Herein a simple approach to fabricate hybrid nanomaterials based on dendrimers as polymeric stabilizers for the preparation of silver nanoparticles in aqueous medium were presented. Solutions of these functional nanomaterials were used as finishing agents to produce antimicrobial textiles. The concept was verified on different generations of hydroxyl-terminated dendrimers with increasing size from first to fifth generation. The application was tested on two different fabrics types made of cotton and polyester. The thermal fixation was performed at 120 or 160°C. The antimicrobial properties of the treated fabrics were investigated using the bacteriaEscherichia coliandStaphylococcus aureus. The antimicrobial effect of the treated fabrics was found which significant correlates not only with the amount of the silver content in the finishing agent but also with size of the generated Ag-nanoparticles. Furthermore, the results confirmed that the antimicrobial effect rises with increasing the dendrimers’ generations suggested due to decreasing the size of the formed silver particles. By changing both parameters thermal fixation and dendrimers’ generations, the strength of the antimicrobial effect can be controlled in a wide manner. This could be advantageous for applications demanding a textile with a certain antimicrobial effect. [ABSTRACT FROM AUTHOR]

Conductive polymer poly-3-hexylthiophene (P3HT) needles were self-assembled using a second component (indandione derivatives) as a linking agent to enhance their long range alignment. The morphologies of the hybrid organic/organic materials were characterized by transmission electron microscopy (TEM). Both linear and branched structures could be produced, with the degree of branching depending upon the linker used. Incorporation of indandione derivatives broadened the UV absorbance band of P3HT without significant change to its photoluminescence. This hybrid material could open a promising avenue in photovoltaic applications due to its interesting morphologies and optical properties. [ABSTRACT FROM AUTHOR]

The thermal properties, crystallization, and morphology of amphiphilic poly( D-lactide)- b-poly( N, N-dimethylamino-2-ethyl methacrylate) (PDLA- b-PDMAEMA) and poly ( L-lactide)- b-poly( N, N-dimethylamino-2-ethyl methacrylate) (PLLA- b-PDMAEMA) copolymers were studied and compared to those of the corresponding poly(lactide) homopolymers. Additionally, stereocomplexation of these copolymers was studied. The crystallization kinetics of the PLA blocks was retarded by the presence of the PDMAEMA block. The studied copolymers were found to be miscible in the melt and the glassy state. The Avrami theory was able to predict the entire crystallization range of the PLA isothermal overall crystallization. The melting points of PLDA/PLLA and PLA/PLA- b-PDMAEMA stereocomplexes were higher than those formed by copolymer mixtures. This indicates that the PDMAEMA block is influencing the stability of the stereocomplex structures. For the low molecular weight samples, the stereocomplexes particles exhibited a conventional disk-shape structure and, for high molecular weight samples, the particles displayed unusual star-like shape morphology. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1397-1409, 2011 [ABSTRACT FROM AUTHOR]