Multifunctional Constructs Research Articles

Multifunctional Thio-Stabilized Gold Nanoparticles for Near-Infrared Fluorescence Detection and Imaging of Activated Caspase-3.

Gold nanoparticles (AuNPs) are commonly used in nanomedicine because of their unique spectral properties, chemical and biological stability, and ability to quench the fluorescence of organic dyes attached to their surfaces. However, the utility of spherical AuNPs for activatable fluorescence sensing of molecular processes have been confined to resonance-matched fluorophores in the 500 nm to 600 nm spectral range to maximize dye fluorescence quenching efficiency. Expanding the repertoire of fluorophore systems into the NIR fluorescence regimen with emission >800 nm will facilitate the analysis of multiple biological events with high detection sensitivity. The primary goal of this study is to determine if spherical AuNP-induced radiative rate suppression of non-resonant near-infrared (NIR) fluorescent probes can serve as a versatile nanoconstruct for highly sensitive detection and imaging of activated caspase-3 in aqueous media and cancer cells. This required the development of activatable NIR fluorescence sensors of caspase-3 designed to overcome the nonspecific degradation and release of the surface coatings in aqueous media. We harnessed the fluorescence-quenching properties and multivalency of spherical AuNPs to develop AuNP-templated activatable NIR fluorescent probes to detect activated caspase-3, an intracellular reporter of early cell death. Freshly AuNPs were coated with a multifunctional NIR fluorescent dye-labeled peptide (LS422) consisting of an RGD peptide sequence that targets αvβ3-integrin protein (αvβ3) on the surface of cancer cells to mediate the uptake and internalization of the sensors in tumor cells; a DEVD peptide sequence for reporting the induction of cell death through caspase-3 mediated NIR fluorescence enhancement; and a multidentate hexacysteine sequence for enhancing self-assembly and stabilizing the multifunctional construct on AuNPs. The integrin binding affinity of LS422 and caspase-3 kinetics were determined by a radioligand competitive binding and fluorogenic peptide assays, respectively. Detection of intracellular caspase-3, cell viability, and the internalization of LS422 in cancer cells were determined by confocal NIR fluorescence spectroscopy and microscopy. Narrow size AuNPs (13 nm) were prepared and characterized by transmission electron microscopy and dynamic light scattering. When assembled on the AuNPs, the binding constant of LS422 for αvβ3 improved 11-fold from 13.2 nM to 1.2 nM. Whereas the catalytic turnover of caspase-3 by LS422-AuNPs was similar to the reference fluorogenic peptide, the binding affinity for the enzyme increased by a factor of 2. Unlike the αvβ3 positive, but caspase-3 negative breast cancer MCF-7 cells, treatment of the αvβ3 and caspase-3 positive lung cancer A549 cells with Paclitaxel showed significant fluorescence enhancement within 30 minutes, which correlated with caspase-3 specific activation of LS422-AuNPs fluorescence. Incorporation of a 3.5 mW NIR laser source into our spectrofluorometer increased the detection sensitivity by an order of magnitude (limit of detection ~0.1 nM of cypate) and significantly decreased the signal noise relative to a xenon lamp. This gain in sensitivity enabled the detection of substrate hydrolysis at a broad range of inhibitor concentrations without photobleaching the cypate dye. The multifunctional AuNPs demonstrate the use of a non-resonant quenching strategy to design activatable NIR fluorescence molecular probes. The nanoconstruct offers a selective reporting method for detecting activated caspase-3, imaging of cell viability, identifying dying cells, and visualizing the functional status of intracellular enzymes. Performing these tasks with NIR fluorescent probes creates an opportunity to translate the in vitro and cellular analysis of enzymes into in vivo interrogation of their functional status using deep tissue penetrating NIR fluorescence analytical methods.

Modifications to improve properties of gypsum ceiling composites as multifunctional construction by embedding Typha angustifolia fiber and natural rubber latex compound

Modifications to improve the physical, thermal, and mechanical properties of gypsum ceiling composites can be made by adding bio-fillers. Adding 1 and 3 wt% of Typha angustifolia fiber in 1D, 2D, or 3D fiber orientations, and adding 20 or 50 wt% natural rubber-latex compound were embedded into gypsum ceiling composites using a casting process. The gypsum ceiling composites added 1 wt% Typha angustifolia fiber 3D orientation (Formula 6, G-3D-1 F) resulted in optimum conditions with high compressive stress, high nail tensile resistance, high thermal shock resistance, low thermal conductivity, and a light weight with values of 315.17 ± 27.40 N, 92.10 ± 3.78 N. The received samples (G-3D-1 F) were no cracking and fracturing after autoclave testing, and 0.0796 ± 0.0005 W/m.K, respectively, better than those of the reference sample (Formula1, G-ref). Furthermore, the received samples were compared to commercial insulation materials such as concrete block, earthenware brick, light concrete brick, and cement brick with thermal conductivity values of approximately 0.546, 0.473, 0.180, and 0.126 W/m.K, respectively. The tested gypsum ceiling composites can be applied for thermal insulation and as decorative materials for construction and building to reduce energy consumption. In addition, the developed gypsum ceiling composites are easy fabrication and operation, non-toxic, inexpensive, and light weight.

Foam-filling techniques to enhance mechanical behaviors of woven lattice truss sandwich panels

Woven lattice truss sandwich panel (WLTSP) is a novel lightweight multifunctional construction material. To further improve its compression strength and bending resistance, two foam-filling schemes were applied to strengthen the WLTSP. Flatwise compression and three-point bending experiments were performed to reveal the deformation, the failure, the energy absorption, and the foam-filling effect. The results show that foam-filling methods can effectively restrain the flexural and shear deformation of the fiber pillars in the woven-core and increase the flatwise compression resistance of the WLTSP. Foam-filling scheme can effectively increase the flexure ductility and failure load through enhancing the shear and indentation resistances of truss core of the WLTSP. All experiments reveal that the foam-filled woven lattice truss could effectively improve the crashworthiness of the WLTSP. Concrete foam can increase the total energy absorption (EA) but reduce the specific energy absorption (SEA). Polyurethane foam is a much better core-filling material to improve the crashworthiness of WLTSPs.

Innovation and characterization of a new multifunctional light weight low cost construction material from foamed rubber blend

New amendment in vulcanization process was used to prepare foamed rubber with enhanced physical properties other than expected and desirable thermal insulation properties. In this work the influence of foaming agent loaded NR/ SBR on thermal conductivity, density, water absorption swelling and mechanical properties was investigated. Different concentrations of foaming agent (2, 4, 6, 8, and 10 phr) were added to rubber matrix. The morphology of selected samples was characterized using scan electron microscope (SEM). An experimental investigation was carried out to obtain low cost multifunctional construction material with desirable mechanical and thermal insulation properties. The addition of foaming agent led to a decrease in thermal conductivity and density values until the concentration of 8phr after that their values slightly changed. It was also observed that mechanical properties of blends were improved with the addition of foaming agent. The optimum concentration was found to be 8phr for all measurements

A sequential 3D bioprinting and orthogonal bioconjugation approach for precision tissue engineering

Recent advances in 3D bioprinting have transformed the tissue engineering landscape by enabling the controlled placement of cells, biomaterials, and bioactive agents for the biofabrication of living tissues and organs. However, the application of 3D bioprinting is limited by the availability of cytocompatible and printable biomaterials that recapitulate properties of native tissues. Here, we developed an integrated 3D projection bioprinting and orthogonal photoconjugation platform for precision tissue engineering of tailored microenvironments. By using a photoreactive thiol-ene gelatin bioink, soft hydrogels can be bioprinted into complex geometries and photopatterned with bioactive moieties in a rapid and scalable manner via digital light projection (DLP) technology. This enables localized modulation of biophysical properties such as stiffness and microarchitecture as well as precise control over spatial distribution and concentration of immobilized functional groups. As such, well-defined properties can be directly incorporated using a single platform to produce desired tissue-specific functions within bioprinted constructs. We demonstrated high viability of encapsulated endothelial cells and human cardiomyocytes using our dual process and fabricated tissue constructs functionalized with VEGF peptide mimics to induce guided endothelial cell growth for programmable vascularization. This work represents a pivotal step in engineering multifunctional constructs with unprecedented control, precision, and versatility for the rational design of biomimetic tissues.

Benefits of the ecosystem services provided by urban green infrastructures: Differences between perception and measurements

Urban green infrastructures (UGIs) are being increasingly recognized as key providers of ecosystem services (ES) in cities. However, many developing countries still lack the public awareness of the concepts of UGIs and their ES, including the benefit & monetary value of the UGIs’ services, the willingness to pay (WTP) for the UGIs’ services. The relationship between the benefits & monetary value of and the WTP for the services of UGIs has not been extensively investigated. These two aspects were respectively defined as ES supply and as ES demand in the current study, in which their relationship was scientifically described. Meanwhile, the influential factors of the deviation between ES supply and ES demand were explored. Adopting Guangzhou City (China) as a case, the main ES supply of UGIs in three public green spaces including air pollutant removal, daytime temperature reduction, rainwater runoff regulation, and noise abatement was first assessed with field measurements. Further, the main ES demand including people’s preferences, satisfaction, and WTP for the UGIs’ ES was analyzed with survey and statistical analysis. In total, 405 valid questionnaires were distributed to collect the data of ES demand and were analyzed by the nonparametric Kruskal-Wallis H test and a binary logistic regression model. The monetary valuation was used to unify the benefit valuation standards provided by different ESs, so as to more intuitively reflect the contribution of different ESs and compare these with ESs demand which uses WTP as one of the indicators. The results showed significant differences between ES supply and ES demand. The major evidence was that the regulation services could supply most of the ES benefits, while the cultural services were the most demanded by respondents. People had diverse sensitivity to the different types of ES provided by the UGIs. Cultural services were the most easily perceived by the respondents and considered as the top one, followed by regulation services. In addition, the outcome of the survey revealed different criteria regarding ES demand by people, and varying influencing factors for people’s satisfaction and WTP. Benefits, such as education opportunities, entertainment, and health values provided by UGIs in cultural services were more favored by respondents. Last, the statistical analysis confirmed that sociodemographic factors significantly influence people's WTP. This study suggests that UGIs should be oriented towards multifunctional construction, thereby emphasizing the relationship and balance between ecological integrity and social perception.

Self-sensing Piezoresistive Composites Based on Cement Incorporating Low Dosage of Carbon Black Used as Multifunctional Construction Materials

HIGHLIGHTS -Carbon black (CB) particles in nanometric domain can be successfully incorporated in cement matrices in order to obtain special concretes/mortars with self-sensing properties. -Piezorezistivity monitoring of mortars is a non-destructive method used to assess the structural characteristics of composite materials. -The presence of CB in studied mortars provides a specific electrical sensitivity which may change when curing time increases. The paper presents the manufacture and characterization of special mortars based on Portland cement (PC) and a nanopowder with electrical properties (carbon black - CB). These materials were characterized from the point of view of mechanical strengths as well as properties specific for self-sensing materials i.e. variation of electrical signal when applying a mechanical strain. The electrical signal and mechanical strength values are strongly dependent on the composition and microstructure of mortars.The values of electrical resistance are strongly correlated with the composition, morphology and curing time of the mortars. In this study significant changes of the electrical behaviour (piezoresistivity) of the mortars vs. curing time (90 or 180 days) were noticed, so this must be considered in practical applications. The best results were obtained for the mortars with 0.5-3 wt.% CB cured for 180 days.

Mechanical properties and durability performance of fly ash based mortar containing nano- and micro-silica additives

The aim of this paper is to investigate the influence of nano-silica (NS) and micro-silica (MS) on the properties of fly ash based geopolymer mortar. The use of such additives has the potential to provide greener and cheaper concrete with enhanced properties. A screening study was conducted to compare the performance of mortar containing varying percentages of NS and MS (up to 15%). The performance of each specimen was determined through tests on compressive strength, splitting tensile strength, workability, and water absorption. Results indicated that mortar with a dosage of 5% NS shows optimum results in workability and mechanical properties. This is mainly due to the pozzolanic and filling effects of large surface area nanosized particles on the cementitious matrix. Moreover, the effect of 5% NS was investigated for mortars containing different amounts of fly ash (up to 30%) which replaced cement by weight. With the presence of 5% NS, variation in fly ash content has no significant influence on the flowability. Although replacement of cement with fly ash at 10% in the presence of 5% NS decreased the splitting tensile strength, no significant reduction was noticed when compared with control samples (without nanoparticle). Compressive strengths also show significant reduction as the percentage of fly ash increases, however the presence of 5% NS aids in the strength development over 28 days. Observations from this study show the effects of nano-silica and fly ash dosage in the performance of cementitious composites. Thus, the results of this study is beneficial for future applications of nanomaterials in cement-based composites for generation of multifunctional construction materials.

Nanomaterial Patterning in 3D Printing.

The synergistic integration of nanomaterials with 3D printing technologies can enable the creation of architecture and devices with an unprecedented level of functional integration. In particular, a multiscale 3D printing approach can seamlessly interweave nanomaterials with diverse classes of materials to impart, program, or modulate a wide range of functional properties in an otherwise passive 3D printed object. However, achieving such multiscale integration is challenging as it requires the ability to pattern, organize, or assemble nanomaterials in a 3D printing process. This review highlights the latest advances in the integration of nanomaterials with 3D printing, achieved by leveraging mechanical, electrical, magnetic, optical, or thermal phenomena. Ultimately, it is envisioned that such approaches can enable the creation of multifunctional constructs and devices that cannot be fabricated with conventional manufacturing approaches.

Mechanical properties of hybrid triphasic scaffolds for osteochondral tissue engineering

Reproducing the advanced complexity of native tissue by means of the 3D multi-functional construct is a promising tissue engineering approach to osteochondral tissue regeneration. In this study, we present a porous 3D construct composed of three zones responsible for the regeneration of non-calcified cartilage, calcified cartilage and subchondral bone. These three zones of the hybrid were composed of modified biopolymers: (i) alginate (Alg) reinforced by short polylactide (PLA) fibres, (ii) alginate and gelatine methacrylate (GelMA) combined with ß-tricalcium phosphate particles (TCP), (iii) 3D printed polycaprolactone scaffold subsequently modified with the use of an innovative solvent treatment method based on acetone and ultrasound stimulation, respectively. Combining the advanced deposition systems based on: (i) 3D printing coupled with a spray crosslinking system, (ii) an innovative deposition system based on a coaxial-needle extruder, (iii) fused deposition modelling (FDM) connected with post-fabrication treatment, allows us to fabricate the triphasic construct that emulates the structure and properties of the native osteochondral tissue. The aim of the study was to investigate the mechanical properties of the fabricated hybrid and its individual zones. Our results demonstrate the load-bearing capabilities of TC, but nevertheless it should be implanted below the surface line of host cartilage to protect it from strong stresses, at the same time allowing native host tissues to grow into it.

3D bioprinting of triphasic nanocomposite hydrogels and scaffolds for cell adhesion and migration

In this study we describe the first example of 3D bioprinted triphasic chiral nanocomposite (NC) hydrogels/scaffolds to simulate the complex 3D architecture, nano/micro scale topography, and chiral nature of extracellular matrix. These multifunctional constructs are prepared using a 3D bioprinting technique and are composed of three connected hydrogels/scaffolds, two of which are loaded with nanomaterials functionalized with opposite enantiomers of a biomolecule. With these constructs, we direct the migration of cells toward the part of the triphasic chiral NC hydrogels/scaffolds containing the cells’ preferred biomolecule enantiomer.

Multiscale investigation of tensile properties of a TiO2-doped Engineered Cementitious Composite

Abstract Engineered Cementitious Composites (ECC) provides a unique platform to develop high-performance and multifunctional construction materials with strain-hardening properties and exceptional crack control capability. ECC incorporating titanium dioxide (TiO2) nanoparticles has intrinsically embodied photocatalytic properties, such as air-purifying functionality. However, there remains a lack of fundamental knowledge on how the presence of TiO2 nanoparticles affects fiber/matrix interface and macro tensile properties of ECC. There is a need to establish a holistic understanding of the role of TiO2 nanoparticles in ECC at multiple scales. To this end, this study experimentally investigates the effect of TiO2 content (up to 15% of binder) on the fiber/matrix interface and on the tensile properties of ECC. A micromechanical model is used to link the multiscale material properties and interpret the test data of the TiO2-doped ECC. Results show that changes in the macroscopic tensile properties as a result of TiO2 addition can be traced back to the matrix and fiber/matrix interface properties. The research findings provide insights into the underlying mechanisms of tensile property modifications by TiO2 nanoparticles, as well as establishing a reference for the design of photocatalytic ECC for balanced functional and mechanical properties.

Boronic acids as building blocks for the construction of therapeutically useful bioconjugates.

Bioconjugates are multifunctional constructs in which biomolecules like peptides, proteins, vitamins and nucleic acids are endowed with the properties of specific payloads. These constructs recently emerged as a new generation of high-precision therapeutics, with several representatives reaching the market. This success stimulated an intense search for new biocompatible synthetic methodologies to connect both components and to control the bioconjugate's function. Despite the remarkable advances made in this field, most of the technologies developed for the construction of bioconjugates were engineered to yield stable constructs that can endure complex physiological conditions. Because of this, the use of reversible covalent bonds in the synthesis of bioconjugates has been rather overlooked, notwithstanding the potential of this strategy to generate stimuli responsive constructs that may operate in areas like the selective delivery of drugs, live-cell imaging and new theranostic approaches. Boronic acids are a well-known class of reagents that have been widely used in modern synthesis for the formation of C-C and C-heteroatom bonds. Apart from this, boronic acids exhibit an exquisite reversible coordination profile that can be explored as a molecular construction tool featuring specific mechanisms to control the structure and biological properties of bioconjugates. In this review, the use of boronic acids in the construction of therapeutically useful bioconjugates will be discussed, focusing on the molecular mechanisms that allow the use of these reagents as bioconjugation warheads, as central pieces of linker structures and as functional payloads.

THE FORMATION PROCEDURE OF THE ESTIMATED CONSTRUCTION COSTS OF ROOM FUNCTION GROUPS

The article is concerned with the problem of cost estimation for multifunctional construction projects on the stage of pre-investment feasibility study. For addressing issues such as the definition of capital investment unto the property assets the author considers the procedure of construction cost estimation on the base of the cost indicators of room function groups. On a research basis the author has developed the calculation methodology of the cost indicators of room function groups. Room function groups present the assembly of spatially connected facilities and communication passages which are focused on define operations functions accomplishment. There is the procedure of the application of room function groups costs for the definition of the investment volume in building construction in the phase of poorly detailed preliminary design.

Aptamers: novelty tools for cancer biology

Although the term ‘cancer’ was still over two thousand years away of being coined, the first known cases of the disease date back to about 3000BC, in ancient Egypt. Five thousand years later, still lacking a cure, it has become one of the leading causes of death, killing over half a dozen million people yearly. So far, monoclonal antibodies are the most successful immune-therapy tools when it comes to fighting cancer. The number of clinical trials that use them has been increasing steadily during the past few years, especially since the Food and Drug Administration greenlit the use of the first immune-checkpoint blockade antibodies. However, albeit successful, this approach does come with the cost of auto-inflammatory toxicity. Taking this into account, the development of new therapeutic reagents with low toxicity becomes evident, particularly ones acting in tandem with the tools currently at our disposal. Ever since its discovery in the early nineties, aptamer technology has been used for a wide range of diagnostic and therapeutic applications. With similar properties to those of monoclonal antibodies, such as high-specificity of recognition and high-affinity binding, and the advantages of being developed using in vitro selection procedures, aptamers quickly became convenient building blocks for the generation of multifunctional constructs. In this review, we discuss the steps involved in the in vitro selection process that leads to functional aptamers - known as Systematic Evolution of Ligands by Exponential Enrichment - as well as the most recent applications of this technology in diagnostic and treatment of oncological illnesses. Moreover, we also suggest ways to improve such use.

Application and Mechanics Analysis of Multi-function Construction Platforms in Prefabricated

Application and Mechanics Analysis of Multi-function Construction Platforms in Prefabricated

Ultrahigh Performance Nanoengineered Graphene–Concrete Composites for Multifunctional Applications

AbstractThere is a constant drive for development of ultrahigh performance multifunctional construction materials by the modern engineering technologies. These materials have to exhibit enhanced durability and mechanical performance, and have to incorporate functionalities that satisfy multiple uses in order to be suitable for future emerging structural applications. There is a wide consensus in the research community that concrete, the most used construction material worldwide, has to be engineered at the nanoscale, where its chemical and physiomechanical properties can be truly enhanced. Here, an innovative multifunctional nanoengineered concrete showing an unprecedented range of enhanced properties when compared to standard concrete, is reported. These include an increase of up to 146% in the compressive and 79.5% in the flexural strength, whilst at the same time an enhanced electrical and thermal performance is found. A surprising decrease in water permeability by nearly 400% compared to normal concrete makes this novel composite material ideally suitable for constructions in areas subject to flooding. The unprecedented gamut of functionalities that are reported in this paper are produced by the addition of water‐stabilized graphene dispersions, an advancement in the emerging field of nanoengineered concrete which can be readily applied in a more sustainable construction industry.

Acoustic emission investigation of the effect of graphene on the fracture behavior of cement mortars

Graphene-modified cements are envisioned as next-generation multifunctional construction materials with superior mechanical performance and smart strain sensing capabilities. The presence study aims to fill the current lack of knowledge on the effect of graphene presence on the fracture behavior and mechanical response of nanoplatelet-modified mortars. Pure bending, compression and fracture tests with simultaneous AE monitoring were carried out on specimens fabricated by introduction of pure few-layer graphene nanoplatelets in the mixture by aid of a superplasticizer doubling as surfactant. The nanoplatelets were found responsible for dramatic improvements of the order of 1700% in the fracture energy requirements of the mortars. The improvements were independently validated by acoustic emission data which also highlighted the very high energy dissipation potential of graphene nanoplatelets which endowed ductility to the highly-brittle plain material and indicated a shift in the fracture mode of the mortars from shear to tensile attributed exclusively to platelet presence.

Principles for the formation of an effective concept of multifunctional high-rise construction investment projects

Investment projects of high-rise construction have a number of features that determine specific risks and additional opportunities that require analysis and accounting in the formation of an effective project concept. The most significant features of high-rise construction include long construction time, complexity of technical and technological solutions, complexity of decisions on the organization of construction and operation, high cost of construction and operation, complexity in determining the ratio of areas designed to accommodate different functional areas, when organizing and coordinating the operation of the facility, with internal zoning. Taking into account the specificity of high-rise construction, among the factors determining the effectiveness of projects, it is advisable to consider as key factors: organizational, technological and investment factors. Within the framework of the article, the author singled out key particular functions for each group of factors under consideration, and also developed a system of principles for the formation of an effective concept of multifunctional high-rise construction investment projects, including the principle of logistic efficiency, the principle of optimal functional zoning, the principle of efficiency of equipment use, the principle of optimizing technological processes, the principle maximization of income, the principle of fund management, the principle of risk management . The model of formation of an effective concept of investment projects of multifunctional high-rise construction developed by the author can contribute to the development of methodological tools in the field of managing the implementation of high-rise construction projects, taking into account their specificity in the current economic conditions.

Specific features of modern multifunctional high-rise building construction

The article analyzes the main reasons for the development of high-rise building construction the most important of which-is a limitation of the urban areas and, consequently, the high price of land reserved for construction. New engineering and compositional solutions for the creation of new types of buildings are considered - complex technical designs of a large number of storeys completely meet the new requirements for safety and comfort. Some peculiarities of designing high-rise buildings and searching for optimal architectural and planning solutions are revealed since, with external architectural simplicity, high-rise buildings have complex structural and technological and space-planning solutions. We consider the specific features of a high-rise housing in various countries around the world, including Russia, such as the layout of the multi-storey residential buildings, depending on the climatic characteristics of the regions, assessment of the geological risk of the construction site, the choice of parameters and functional purpose of the sections of the territory of high-rise construction, location of the town-planning object for substantiating the overall dimensions of the building, assessment of changes aeration and engineering and hydrological conditions of the site. A special place in the article on the problems of improvement of the territory, the device of courtyards, landscaping, the device of playing and sports grounds. The main conclusion in the article is the following problem - when developing high-rise housing construction, the development of high-rise housing, and an increase in the population density in the territory of large cities of Russia, necessary to create a comfortable and safe level of residents living and not a decrease, but an improvement in the quality of the urban environment.