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He ZH, Ni YQ, Shi JY, Rong H, Tao HY, Jamal AS. Upcycling textile sludge into magnesium oxychloride cement: Physical properties, microstructure, and leaching behavior. Sci Total Environ 2024; 924:171416. [PMID: 38447715 DOI: 10.1016/j.scitotenv.2024.171416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Revised: 02/04/2024] [Accepted: 02/29/2024] [Indexed: 03/08/2024]
Abstract
Textile sludge is a by-product produced during the wastewater treatment process in the textile printing and dyeing industry. Textile sludge is rich in heavy metal elements, which makes it a potential risk to the surrounding environment. This study designs a magnesium oxychloride cement (MOC) components to solidify harmful substances in textile sludge and studies the influence of textile sludge ash (TSA) on the mechanical properties and microstructure of MOC samples. The results indicated that adding 5 %-20 % TSA is beneficial for increasing the compressive strength of air-cured MOC paste and improving its water resistance. Meanwhile, the MOC sample shows volume expansion in 168 h, which is related to the further hydration of residual MgO. Incorporating 10 %-20 % TSA substantially increased the volume expansion ratio of the mixture compared to plain MOC sample. In addition, the porosity of TSA-modified MOC after water curing did not change significantly compared to the sample before water curing, while the pore structure of plain MOC after water curing significantly coarsened. This is mainly because TSA reacts with MOC and generates Mg-Al-Cl-Si-H and Mg-Cl-Si-H gels, consequently improving the water stability of MOC sample. At the nanoscale, the 3/5-phase crystal and unreacted MgO content in the 15 % TSA-modified MOC sample is relatively reduced by 7.79 % and 25 %, respectively, compared to the plain sample, but the 13 % gel phase is detected. In addition, the MOC component can effectively solidify heavy metal elements in textile sludge. For the leachate of 20 % TSA-modified MOC paste, the Ni element is not detected, and its solidifying effect on heavy elements such as Zn and Mn exceeded 99 %.
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Affiliation(s)
- Zhi-Hai He
- College of Civil Engineering, Shaoxing University, Shaoxing 312000, China; Key Laboratory of Rock Mechanics and Geohazards of Zhejiang Province, Shaoxing 312000, China
| | - Ya-Qian Ni
- College of Civil Engineering, Shaoxing University, Shaoxing 312000, China
| | - Jin-Yan Shi
- School of Civil Engineering, Central South University, Changsha 410075, China.
| | - Hui Rong
- School of Materials Science and Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Hong-Yu Tao
- Yuanpei College, Shaoxing University, Shaoxing 312000, China
| | - Ahmed Salah Jamal
- Civil Engineering Department, Tishk International University, Erbil 44001, Iraq
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Guatelli-Steinberg D, Renteria C, Grimm JR, Maeret Carpenter I, Arola DD, McGraw WS. How mangabey molar form differs under routine vs. fallback hard-object feeding regimes. PeerJ 2023; 11:e16534. [PMID: 38099313 PMCID: PMC10720418 DOI: 10.7717/peerj.16534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 11/07/2023] [Indexed: 12/17/2023] Open
Abstract
Background Components of diet known as fallback foods are argued to be critical in shaping primate dental anatomy. Such foods of low(er) nutritional quality are often non-preferred, mechanically challenging resources that species resort to during ecological crunch periods. An oft-cited example of the importance of dietary fallbacks in shaping primate anatomy is the grey-cheeked mangabey Lophocebus albigena. This species relies upon hard seeds only when softer, preferred resources are not available, a fact which has been linked to its thick dental enamel. Another mangabey species with thick enamel, the sooty mangabey Cercocebus atys, processes a mechanically challenging food year-round. That the two mangabey species are both thickly-enameled suggests that both fallback and routine consumption of hard foods are associated with the same anatomical feature, complicating interpretations of thick enamel in the fossil record. We anticipated that aspects of enamel other than its thickness might differ between Cercocebus atys and Lophocebus albigena. We hypothesized that to function adequately under a dietary regime of routine hard-object feeding, the molars of Cercocebus atys would be more fracture and wear resistant than those of Lophocebus albigena. Methods Here we investigated critical fracture loads, nanomechanical properties of enamel, and enamel decussation in Cercocebus atys and Lophocebus albigena. Molars of Cercopithecus, a genus not associated with hard-object feeding, were included for comparison. Critical loads were estimated using measurements from 2D µCT slices of upper and lower molars. Nanomechanical properties (by nanoindentation) and decussation of enamel prisms (by SEM-imaging) in trigon basins of one upper second molar per taxon were compared. Results Protocone and protoconid critical fracture loads were significantly greater in Cercocebus atys than Lophocebus albigena and greater in both than in Cercopithecus. Elastic modulus, hardness, and elasticity index in most regions of the crown were greater in Cercocebus atys than in the other two taxa, with the greatest difference in the outer enamel. All taxa had decussated enamel, but that of Cercocebus atys uniquely exhibited a bundle of transversely oriented prisms cervical to the radial enamel. Quantitative comparison of in-plane and out-of-plane prism angles suggests that decussation in trigon basin enamel is more complex in Cercocebus atys than it is in either Lophocebus albigena or Cercopithecus cephus. These findings suggest that Cercocebus atys molars are more fracture and wear resistant than those of Lophocebus albigena and Cercopithecus. Recognition of these differences between Cercocebus atys and Lophocebus albigena molars sharpens our understanding of associations between hard-object feeding and dental anatomy under conditions of routine vs. fallback hard-object feeding and provides a basis for dietary inference in fossil primates, including hominins.
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Affiliation(s)
- Debbie Guatelli-Steinberg
- Department of Anthropology, The Ohio State University, Columbus, OH, United States of America
- School of Anthropology and Conservation, University of Kent, Canterbury, Kent, United Kingdom
| | - Cameron Renteria
- Department of Materials Science and Engineering, University of Washington, Seattle, WA, United States of America
- Department of Oral Health Sciences, School of Dentistry, University of Washington, Seattle, WA, United States of America
| | - Jack R. Grimm
- Department of Materials Science and Engineering, University of Washington, Seattle, WA, United States of America
| | - Izabela Maeret Carpenter
- Department of Materials Science and Engineering, University of Washington, Seattle, WA, United States of America
| | - Dwayne D. Arola
- Department of Materials Science and Engineering, University of Washington, Seattle, WA, United States of America
- Department of Oral Health Sciences, School of Dentistry, University of Washington, Seattle, WA, United States of America
- Department of Mechanical Engineering, University of Washington, Seattle, WA, United States of America
- Department of Restorative Dentistry, School of Dentistry, University of Washington, Seattle, WA, United States of America
| | - W. Scott McGraw
- Department of Anthropology, The Ohio State University, Columbus, OH, United States of America
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Nevárez-Rascón A, Leal-Perez JE, Talamantes RP, Auciello O, Hurtado-Macías A. Nanomechanical properties of kidney stones, gallstones and oral stones compared with tap water scale by depth sensing indentation. J Mech Behav Biomed Mater 2023; 147:106131. [PMID: 37774441 DOI: 10.1016/j.jmbbm.2023.106131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 09/13/2023] [Accepted: 09/18/2023] [Indexed: 10/01/2023]
Abstract
This article focuses on a description of research performed to identify structural and mechanical properties differences between calculi in stones, such as gallstones, kidney stones, dental tartar, and saliva gland sialolite, were analyzed and compared with tap water stone, in order to set interrelations. In this study, biological hard pebble-like structures were analyzed and compared among them using Scanning Electron Microscopy (SEM), X-Ray diffraction (XRD), and Atomic Force Microscopy (AFM). In addition, Nanoindentation was used to obtain values as example in kidney stones the in; stiffness S = 27,827 ± 620 N/nm elastic modulus E = 27.3 ± 4.5 GPa, hardness H = 1.5 ± 0.5 GPa. Samples with the highest amounts of calcium and magnesium oxides were; Tap water stone (39.60%), followed by dental tartar (39.40%), saliva gland sialolite (29.20%), kidney stones (27.70%), and lastly the gallstones (0.30%). Kidney stones showed in particular, whewellite and kaoulinite crystallographic phases, that confers characteristics of greater crystallization with respect to the other stones. Kidney stones positioned in the major hardness stone in human body with 1.5 GPa. In general, samples with the highest amount of calcium oxides, also showed the highest mechanical properties of H and E. Microstructural characteristics and nano-hardness of tap water stone from drinking water where similar to those of dental tartar and saliva gland sialolite, more research still required to associate health concerns and tap water scale derived from drinking water known as hardwater.
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Affiliation(s)
- A Nevárez-Rascón
- Research and Graduate Department. Facultad de Odontología, Universidad Autónoma de Chihuahua, Pascual Orozco y Avenida Universidad S/n, C.P, 31000, Chihuahua, Chihuahua, Mexico; Department of Metallurgy and Structural Integrity, National Nanotechnology Laboratory Centro de Investigación en Materiales Avanzados S.C, Chihuahua, Chihuahua, Mexico
| | - J E Leal-Perez
- Universidad Autónoma de Sinaloa, Gral. Ángel Flores S/N, Fracc. Las Fuentes, Los Mochis, Sin, C.P. 81223, Mexico
| | - R P Talamantes
- Department of Metallurgy and Structural Integrity, National Nanotechnology Laboratory Centro de Investigación en Materiales Avanzados S.C, Chihuahua, Chihuahua, Mexico
| | - O Auciello
- University of Texas at Dallas, Departments of Materials Science and Engineering and Boingineering, 800 W. Campbell Rd., RL10, Richardson, TX, 75080-3021, USA
| | - A Hurtado-Macías
- Department of Metallurgy and Structural Integrity, National Nanotechnology Laboratory Centro de Investigación en Materiales Avanzados S.C, Chihuahua, Chihuahua, Mexico.
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Zhou J, Ng BF, Han N, Chen L, Wang Z, Li X, Zou M. Structure and mechanical properties of ladybird elytra as biological sandwich panels. J Mech Behav Biomed Mater 2023; 143:105917. [PMID: 37216753 DOI: 10.1016/j.jmbbm.2023.105917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/13/2023] [Accepted: 05/15/2023] [Indexed: 05/24/2023]
Abstract
The armour of the ladybird, elytra, protect the body from injury and are well-adapted to flight. However, experimental methods to decipher their mechanical performances had been challenging due to the small size, making it unclear how the elytra balance mass and strength. Here, we provide insights to the relationship between the microstructure and multifunctional properties of the elytra by means of structural characterization, mechanical analysis and finite element simulations. Micromorphology analysis on the elytron revealed the thickness ratio of the upper lamination, middle layer and lower lamination is approximately 51:139:7. The upper lamination had multiple cross fibre layers and the thickness of each fibre layer is not the same. In addition, the tensile strength, elastic modulus, fracture strain, bending stiffness and hardness of elytra were obtained through in-situ tensile and nanoindentation-bending under the influence of multiple loading conditions, which also serve as references for finite element models. The finite element model revealed that structural factors such as thickness of each layer, angle of fibre layer and trabeculae are key to affecting the mechanical properties, but the effect is different. When the thickness of upper, middle and lower layers is the same, the tensile strength provided by unit mass of the model is 52.78% lower than that provided by elytra. These findings broaden the relationship between the structural and mechanical properties of the ladybird elytra, and are expected to inspire the development of sandwich structures in biomedical engineering.
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Affiliation(s)
- Jianfei Zhou
- Key Lab of Bionic Engineering, Ministry of Education, Jilin University, Changchun, 130022, China; School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue 639798, Singapore
| | - Bing Feng Ng
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue 639798, Singapore
| | - Na Han
- Key Lab of Bionic Engineering, Ministry of Education, Jilin University, Changchun, 130022, China
| | - Lining Chen
- Key Lab of Bionic Engineering, Ministry of Education, Jilin University, Changchun, 130022, China
| | - Zhaoyang Wang
- Key Lab of Bionic Engineering, Ministry of Education, Jilin University, Changchun, 130022, China
| | - Xiujuan Li
- Key Lab of Bionic Engineering, Ministry of Education, Jilin University, Changchun, 130022, China
| | - Meng Zou
- Key Lab of Bionic Engineering, Ministry of Education, Jilin University, Changchun, 130022, China.
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Radiom M, Keys T, Turgay Y, Ali A, Preet S, Chesnov S, Lutz-Bueno V, Slack E, Mezzenga R. Mechanical tuning of virus-like particles. J Colloid Interface Sci 2023; 634:963-971. [PMID: 36571858 DOI: 10.1016/j.jcis.2022.12.090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 12/18/2022] [Accepted: 12/18/2022] [Indexed: 12/24/2022]
Abstract
HYPOTHESIS Virus-like particles (VLPs) are promising scaffolds for developing mucosal vaccines. For their optimal performance, in addition to design parameters from an immunological perspective, biophysical properties may need to be considered. EXPERIMENTS We investigated the mechanical properties of VLPs scaffolded on the coat protein of Acinetobacter phage AP205 using atomic force microscopy and small angle X-ray scattering. FINDINGS Investigations showed that AP205 VLP is a tough nanoshell of stiffness 93 ± 23 pN/nm and elastic modulus 0.11 GPa. However, its mechanical properties are modulated by attaching muco-inert polyethylene glycol to 46 ± 10 pN/nm and 0.05 GPa. Addition of antigenic peptides derived from SARS-CoV2 spike protein by genetic fusion increased the stiffness to 146 ± 54 pN/nm although the elastic modulus remained unchanged. These results, which are interpreted in terms of shell thickness and coat protein net charge variations, demonstrate that surface conjugation can induce appreciable changes in the biophysical properties of VLP-scaffolded vaccines.
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Affiliation(s)
- Milad Radiom
- Laboratory of Food Immunology, Institute of Food, Nutrition and Health, ETH Zürich, Zürich, Switzerland; Laboratory of Food and Soft Materials, Institute of Food, Nutrition and Health, ETH Zürich, Zürich, Switzerland.
| | - Tim Keys
- Laboratory of Food Immunology, Institute of Food, Nutrition and Health, ETH Zürich, Zürich, Switzerland
| | - Yagmur Turgay
- Laboratory of Food Immunology, Institute of Food, Nutrition and Health, ETH Zürich, Zürich, Switzerland
| | - Ahmed Ali
- Laboratory of Food Immunology, Institute of Food, Nutrition and Health, ETH Zürich, Zürich, Switzerland
| | - Swapan Preet
- Laboratory of Food Immunology, Institute of Food, Nutrition and Health, ETH Zürich, Zürich, Switzerland
| | - Serge Chesnov
- University of Zürich/ETH Zürich, Functional Genomics Centre Zürich, Zürich, Switzerland
| | | | - Emma Slack
- Laboratory of Food Immunology, Institute of Food, Nutrition and Health, ETH Zürich, Zürich, Switzerland.
| | - Raffaele Mezzenga
- Laboratory of Food and Soft Materials, Institute of Food, Nutrition and Health, ETH Zürich, Zürich, Switzerland.
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Negrini M, Batson PB, Smith AM, Smith SAF, Prior DJ, Henry H, Li KC, Tamberg Y. Understanding the crystallographic and nanomechanical properties of bryozoans. J Struct Biol 2022; 214:107882. [PMID: 35850322 DOI: 10.1016/j.jsb.2022.107882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 07/08/2022] [Accepted: 07/12/2022] [Indexed: 11/23/2022]
Abstract
This study examines how microscale differences in skeletal ultrastructure affect the crystallographic and nanomechanical properties of two related bryozoan species: (i) Hornera currieae, which is found at relatively quiescent depths of c. 1000 m, and (ii) Hornera robusta, which lives at depths of 50-400 m where it is exposed to currents and storm waves. Microstructural and Electron Backscatter Diffraction (EBSD) observations show that in both species the secondary walls are composed of low-Mg calcite crystallites that grow with their c-axes perpendicular to the wall. Branches in H. currieae develop a strong preferred orientation of the calcite c-axes, while in H. robusta the c-axes are more scattered. Microstructural observations suggest that the degree of scattering is controlled by the underlying morphology of the skeletons: in H. currieae the laminated branch walls are smooth and relatively uninterrupted, whereas the wall architecture of H. robusta is modified by numerous deflections, forming pustules and ridges associated with microscopic tubules. Modelling of the Young's modulus and measurements of nanoindentation hardness indicate that the observed scattering of the crystallite c-axes affects the elastic modulus and nanohardness of the branches, and therefore controls the mechanical properties of the skeletal walls. At relatively high pressure in deep waters, the anisotropic skeletal architecture of H. currieae is aimed at concentrating elasticity normal to the skeleton wall. In comparison, in the relatively shallow and active hydrographic regime of the continental shelf, the elastically isotropic skeleton of H. robusta is designed to increase protection from external predators and stronger omni-directional currents.
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Wychowaniec JK, Moffat J, Saiani A. Quantitative nanomechanical properties evaluation of a family of β-sheet peptide fibres using rapid bimodal AFM. J Mech Behav Biomed Mater 2021; 124:104776. [PMID: 34479107 DOI: 10.1016/j.jmbbm.2021.104776] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/16/2021] [Accepted: 08/10/2021] [Indexed: 11/20/2022]
Abstract
Self-assembling peptides have become important building blocks for materials design (e.g. hydrogels) and play a crucial role in a range of diseases including Alzheimer and Parkinson. In this context, accessing the nanomechanical properties of ubiquitous β-sheet rich nanofibres (e.g.: amyloids) is key to the formulation of materials and design of therapies. Although the bulk mechanical properties of hydrogels can easily be accessed using common techniques and equipment, the mechanical properties of their constituent fibres, in particular if with radii in the nanometre scale, are more challenging to measure and estimate. In this work we show for the first time how the rapid nanomechanical mapping technique: amplitude modulation-frequency modulation (AM-FM), can be used to determine the heights, Young's moduli and viscosity coefficients of a series of β-sheet peptide nanofibres with high statistical confidence. Our results show how peptide sequence and in particular length, charge and interaction with the substrate affect the viscoelastic properties of the peptide fibres.
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Pu J, Wang L, Zhang W, Ma J, Zhang X, Putnis CV. Organically-bound silicon enhances resistance to enzymatic degradation and nanomechanical properties of rice plant cell walls. Carbohydr Polym 2021; 266:118057. [PMID: 34044915 DOI: 10.1016/j.carbpol.2021.118057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 04/02/2021] [Accepted: 04/05/2021] [Indexed: 12/31/2022]
Abstract
Plant cell walls exhibit excellent mechanical properties, which form the structural basis for sustainable bioresources and multifunctional nanocelluloses. The wall nanomechanical properties of living cells through covalent modifications of hybrid inorganic elements, such as silicon, may confer significant influence on local mechano-response and enzymatic degradation. Here, we present a combination of ex situ measurements of enzyme-released oligosaccharide fragments using MALDI-TOF MS and in situ atomic force microscopy (AFM) imaging through PeakForce quantitative nanomechanical mapping of tip-functionalized single-molecule enzyme-polysaccharide substrate recognition and the nanoscale dissolution kinetics of individual cellulose microfibrils of living rice (Oryza sativa) cells following silicate cross-linking of cell wall xyloglucan. We find that xyloglucan-bound silicon enhances the resistance to degradation by cellulase and improves the wall nanomechanical properties in the elastic modulus at the single-cell level. The findings establish a direct link between an inorganic element of silicon and the nanoscale architecture of plant cell wall materials for sustainable utilization.
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Affiliation(s)
- Junbao Pu
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China
| | - Lijun Wang
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China.
| | - Wenjun Zhang
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China.
| | - Jie Ma
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China
| | - Xiuqing Zhang
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China
| | - Christine V Putnis
- Institut für Mineralogie, University of Münster, 48149, Münster, Germany; School of Molecular and Life Science, Curtin University, 6845, Perth, Australia
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Song Z, Tong J, Yan Y, Wu W, Tian L, Sun J. Combined effects of wrinkled vein structures and nanomechanical properties on hind wing deformation. Micron 2021; 140:102965. [PMID: 33130546 DOI: 10.1016/j.micron.2020.102965] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 10/14/2020] [Accepted: 10/14/2020] [Indexed: 01/31/2023]
Abstract
The veins in the hind wings of the Asian ladybird beetle (Harmonia axyridis) play active roles in flight and in the folding/unfolding of the hind wing. Wrinkled vein structures are located within the bending zone and are used for folding the hind wing. This paper investigates the coupled effect of wrinkled vein structures within the hind wing of H. axyridis on its deformation. Based on the nanomechanical properties of the veins, morphology of the hind wing, surface structures of the veins, and microstructures of the cross sections (including the veins and wing membranes), four 3-D coupling models (Model I and Model II: variably reduced-modulus veins with and without wrinkles, respectively; Model III and Model IV: uniformly reduced-modulus veins with and without wrinkles, respectively) are established. Relative to the bending and twisting model shapes, Model I has much more flexibility during passive deformation to control wing deformations. The simulation results show that both the wrinkled structures in the bending zone and the variably reduced modulus of the veins contribute to the flight performance (the bending and twisting deformations) of the hind wings, which has important implications for the design of the deployable wings of micro air vehicles (MAVs).
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Zafeiris K, Brasinika D, Karatza A, Koumoulos E, Karoussis IK, Kyriakidou K, Charitidis CA. Additive manufacturing of hydroxyapatite-chitosan-genipin composite scaffolds for bone tissue engineering applications. Mater Sci Eng C Mater Biol Appl 2021; 119:111639. [PMID: 33321677 DOI: 10.1016/j.msec.2020.111639] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 09/28/2020] [Accepted: 10/12/2020] [Indexed: 01/07/2023]
Abstract
Additive manufacturing holds promise for the fabrication of three-dimensional scaffolds with precise geometry, to serve as substrates for the guided regeneration of natural tissue. In this work, a bioinspired approach is adopted for the synthesis of hybrid hydroxyapatite hydrogels, which were subsequently printed to form 3D scaffolds for bone tissue engineering applications. These hydrogels consist of hydroxyapatite nanocrystals, biomimetically synthesized in the presence of both chitosan and l-arginine. To improve their mechanical properties, chemical crosslinking was performed using a natural crosslinking agent (genipin), and their rheology was modified by employing an acetic acid/gelatin solution. Regarding the 3D printing process, several parameters (flow, infill and perimeter speed) were studied in order to accurately produce scaffolds with predesigned geometry and micro-architecture, while also applying low printing temperature (15 °C). Following the printing procedure, the 3D scaffolds were freeze dried in order to remove the entrapped solvents and therefore, obtain a porous interconnected network. Evaluation of porosity was performed using micro-computed tomography and nanomechanical properties were assessed through nanoindentation. Results of both characterization techniques, showed that the scaffolds' porosity as well as their modulus values, fall within the corresponding range of the respective values of cancellous bone. The biocompatibility of the 3D printed scaffolds was assessed using MG63 human osteosarcoma cells for 7 days of culturing. Cell viability was evaluated by MTT assay as well as double staining and visualized under fluorescence microscopy, while cell morphology was analyzed through scanning electron microscopy. Biocompatibility tests, revealed that the scaffolds constitute a cell-friendly environment, allowed them to adhere on the scaffolds' surface, increase their population and maintain high levels of viability.
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Mahmoodi B, Wood RJK, Cook RB. Nanomechanical properties of hydroxyapatite like coatings formed by bioactive glasses, arginine and calcium silicate for dentine protection. J Mech Behav Biomed Mater 2020; 105:103702. [PMID: 32090896 DOI: 10.1016/j.jmbbm.2020.103702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 01/30/2020] [Accepted: 02/13/2020] [Indexed: 11/15/2022]
Affiliation(s)
- Behrad Mahmoodi
- National Centre for Advanced Tribology at Southampton (nCATS), Faculty of Engineering and Physical Science, University of Southampton, United Kingdom.
| | - Robert James Knoyle Wood
- National Centre for Advanced Tribology at Southampton (nCATS), Faculty of Engineering and Physical Science, University of Southampton, United Kingdom.
| | - Richard Barker Cook
- National Centre for Advanced Tribology at Southampton (nCATS), Faculty of Engineering and Physical Science, University of Southampton, United Kingdom.
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Kulkarni T, Angom RS, Das P, Bhattacharya S, Mukhopadhyay D. Nanomechanical insights: Amyloid beta oligomer-induced senescent brain endothelial cells. Biochim Biophys Acta Biomembr 2019; 1861:183061. [PMID: 31513781 DOI: 10.1016/j.bbamem.2019.183061] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 09/06/2019] [Indexed: 12/16/2022]
Abstract
Senescent cells accumulate in various peripheral tissues during aging and have been shown to exacerbate age-related inflammatory responses. We recently showed that exposure to neurotoxic amyloid β (Aβ1-42) oligomers can readily induce a senescence phenotype in human brain microvascular endothelial cells (HBMECs). In the present work, we used atomic force microscopy (AFM) to further characterize the morphological properties such as cell membrane roughness and cell height and nanomechanical properties such as Young's modulus of the membrane (membrane stiffness) and adhesion resulting from the interaction between AFM tip and cell membrane in Aβ1-42 oligomer-induced senescent human brain microvascular endothelial cells. Morphological imaging studies showed a flatter and spread-out nucleus in the senescent HBMECs, both characteristic features of a senescent phenotype. Furthermore, the mean cell body roughness and mean cell height were lower in senescent HBMECs compared to untreated normal HBMECs. We also observed increased stiffness and alterations in the adhesion properties in Aβ1-42 oligomer-induced senescent endothelial cells compared to the untreated normal HBMECs suggesting dynamic reorganization of cell membrane. We then show that vascular endothelial growth factor receptor 1 (VEGFR-1) knockdown or overexpression of Rho GTPase Rac 1 in the endothelial cells inhibited senescence and reversed these nanomechanical alterations, confirming a direct role of these pathways in the senescent brain endothelial cells. These results illustrate that nanoindentation and topographic analysis of live senescent brain endothelial cells can provide insights into cerebrovascular dysfunction in neurodegenerative diseases such as Alzheimer's disease.
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Wojas NA, Swerin A, Wallqvist V, Järn M, Schoelkopf J, Gane PAC, Claesson PM. Iceland spar calcite: Humidity and time effects on surface properties and their reversibility. J Colloid Interface Sci 2019; 541:42-55. [PMID: 30682592 DOI: 10.1016/j.jcis.2019.01.047] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 01/10/2019] [Accepted: 01/11/2019] [Indexed: 10/27/2022]
Abstract
Understanding the complex and dynamic nature of calcite surfaces under ambient conditions is important for optimizing industrial applications. It is essential to identify processes, their reversibility, and the relevant properties of CaCO3 solid-liquid and solid-gas interfaces under different environmental conditions, such as at increased relative humidity (RH). This work elucidates changes in surface properties on freshly cleaved calcite (topography, wettability and surface forces) as a function of time (≤28 h) at controlled humidity (≤3-95 %RH) and temperature (25.5 °C), evaluated with atomic force microscopy (AFM) and contact angle techniques. In the presence of humidity, the wettability decreased, liquid water capillary forces dominated over van der Waals forces, and surface domains, such as hillocks, height about 7.0 Å, and trenches, depth about -3.5 Å, appeared and grew primarily in lateral dimensions. Hillocks demonstrated lower adhesion and higher deformation in AFM experiments. We propose that the growing surface domains were formed by ion dissolution and diffusion followed by formation of hydrated salt of CaCO3. Upon drying, the height of the hillocks decreased by about 50% suggesting their alteration into dehydrated or less hydrated CaCO3. However, the process was not entirely reversible and crystallization of new domains continued at a reduced rate.
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Affiliation(s)
- Natalia A Wojas
- RISE Research Institutes of Sweden, Division of Bioscience and Materials - Surface, Process and Formulation, Box 5607, SE-114 86 Stockholm, Sweden; KTH Royal Institute of Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Chemistry, Division of Surface and Corrosion Science, Drottning Kristinas väg 51, SE-100 44 Stockholm, Sweden.
| | - Agne Swerin
- RISE Research Institutes of Sweden, Division of Bioscience and Materials - Surface, Process and Formulation, Box 5607, SE-114 86 Stockholm, Sweden; KTH Royal Institute of Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Chemistry, Division of Surface and Corrosion Science, Drottning Kristinas väg 51, SE-100 44 Stockholm, Sweden
| | - Viveca Wallqvist
- RISE Research Institutes of Sweden, Division of Bioscience and Materials - Surface, Process and Formulation, Box 5607, SE-114 86 Stockholm, Sweden
| | - Mikael Järn
- RISE Research Institutes of Sweden, Division of Bioscience and Materials - Surface, Process and Formulation, Box 5607, SE-114 86 Stockholm, Sweden
| | | | - Patrick A C Gane
- Omya International AG, Baslerstrasse 42, CH-4665 Oftringen, Switzerland; Aalto University, School of Chemical Engineering, Department of Bioproducts and Biosystems, P.O. Box 16300, FI-00076 Aalto, Finland
| | - Per M Claesson
- RISE Research Institutes of Sweden, Division of Bioscience and Materials - Surface, Process and Formulation, Box 5607, SE-114 86 Stockholm, Sweden; KTH Royal Institute of Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Chemistry, Division of Surface and Corrosion Science, Drottning Kristinas väg 51, SE-100 44 Stockholm, Sweden.
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14
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Adhyapak PR, Panchal SV, Murthy AVR. Cholesterol induced asymmetry in DOPC bilayers probed by AFM force spectroscopy. Biochim Biophys Acta Biomembr 2018; 1860:953-9. [PMID: 29408513 DOI: 10.1016/j.bbamem.2018.01.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 01/24/2018] [Accepted: 01/28/2018] [Indexed: 11/21/2022]
Abstract
Cholesterol induced mechanical effects on artificial lipid bilayers are well known and have been thoroughly investigated by AFM force spectroscopy. However, dynamics of cholesterol impingement into bilayers at various cholesterol concentrations and their effects have not been clearly understood. In this paper we present, the effect of cholesterol as a function of its concentration in a simple single component dioleoylphosphatidylcholine (DOPC) bilayer. The nature of measured breakthrough forces on a bilayer with the addition of cholesterol, suggested that it is not just responsible to increase the mechanical stability but also introduces irregularities across the leaflets of the bilayer. This cholesterol induced asymmetry across the (in the inner and outer leaflets) bilayer is related to the phenomena of interleaflet coupling and is a function of cholesterol concentration probed by AFM can provide an unprecedented direction on mechanical properties of lipid membrane as it can be directly correlated to biophysical properties of a cell membrane.
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15
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Preedy EC, Perni S, Prokopovich P. Cobalt and titanium nanoparticles influence on mesenchymal stem cell elasticity and turgidity. Colloids Surf B Biointerfaces 2017; 157:146-156. [PMID: 28586727 DOI: 10.1016/j.colsurfb.2017.05.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 05/07/2017] [Indexed: 12/13/2022]
Abstract
Bone cells are damaged by wear particles originating from total joint replacement implants. We investigated Mesenchymal stem cells (MSCs) nanomechanical properties when exposed to cobalt and titanium nanoparticles (resembling wear debris) of different sizes for up to 3days using AFM nanoindentation; along with flow-cytometry and MTT assay. The results demonstrated that cells exposed to increasing concentrations of nanoparticles had a lower value of elasticity and spring constant without significant effect on cell metabolic activity and viability but some morphological alteration (bleeping). Cobalt induced greater effects than titanium and this is consistent with the general knowledge of cyto-compatibility of the later. This work demonstrates for the first time that metal nanoparticles do not only influence MSCs enzymes activity but also cell structure; however, they do not result in full membrane damage. Furthermore, the mechanical changes are concentration and particles composition dependent but little influenced by the particle size.
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Affiliation(s)
| | - Stefano Perni
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, UK
| | - Polina Prokopovich
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, UK.
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16
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Huang H, Dobryden I, Ihrner N, Johansson M, Ma H, Pan J, Claesson PM. Temperature-dependent surface nanomechanical properties of a thermoplastic nanocomposite. J Colloid Interface Sci 2017; 494:204-214. [PMID: 28160705 DOI: 10.1016/j.jcis.2017.01.096] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 01/24/2017] [Accepted: 01/24/2017] [Indexed: 11/26/2022]
Abstract
In polymer nanocomposites, particle-polymer interactions influence the properties of the matrix polymer next to the particle surface, providing different physicochemical properties than in the bulk matrix. This region is often referred to as the interphase, but detailed characterization of its properties remains a challenge. Here we employ two atomic force microscopy (AFM) force methods, differing by a factor of about 15 in probing rate, to directly measure the surface nanomechanical properties of the transition region between filler particle and matrix over a controlled temperature range. The nanocomposite consists of poly(ethyl methacrylate) (PEMA) and poly(isobutyl methacrylate) (PiBMA) with a high concentration of hydrophobized silica nanoparticles. Both AFM methods demonstrate that the interphase region around a 40-nm-sized particle located on the surface of the nanocomposite could extend to 55-70nm, and the interphase exhibits a gradient distribution in surface nanomechanical properties. However, the slower probing rate provides somewhat lower numerical values for the surface stiffness. The analysis of the local glass transition temperature (Tg) of the interphase and the polymer matrix provides evidence for reduced stiffness of the polymer matrix at high particle concentration, a feature that we attribute to selective adsorption. These findings provide new insight into understanding the microstructure and mechanical properties of nanocomposites, which is of importance for designing nanomaterials.
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Affiliation(s)
- Hui Huang
- Key Laboratory for Colloid and Interface Chemistry of State Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China; KTH Royal Institute of Technology, School of Chemical Sciences and Engineering, Department of Chemistry, Surface and Corrosion Science, Drottning Kristinas väg 51, SE-10044 Stockholm, Sweden.
| | - Illia Dobryden
- KTH Royal Institute of Technology, School of Chemical Sciences and Engineering, Department of Chemistry, Surface and Corrosion Science, Drottning Kristinas väg 51, SE-10044 Stockholm, Sweden
| | - Niklas Ihrner
- KTH Royal Institute of Technology, Department of Fiber and Polymer Technology, Teknikringen 56-58, SE-10044 Stockholm, Sweden
| | - Mats Johansson
- KTH Royal Institute of Technology, Department of Fiber and Polymer Technology, Teknikringen 56-58, SE-10044 Stockholm, Sweden
| | - Houyi Ma
- Key Laboratory for Colloid and Interface Chemistry of State Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Jinshan Pan
- KTH Royal Institute of Technology, School of Chemical Sciences and Engineering, Department of Chemistry, Surface and Corrosion Science, Drottning Kristinas väg 51, SE-10044 Stockholm, Sweden
| | - Per M Claesson
- KTH Royal Institute of Technology, School of Chemical Sciences and Engineering, Department of Chemistry, Surface and Corrosion Science, Drottning Kristinas väg 51, SE-10044 Stockholm, Sweden; SP Technical Research Institute of Sweden, SP Chemistry, Materials and Surfaces, Box 5607, SE-11486 Stockholm, Sweden.
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17
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Wang B, Meyers MA. Seagull feather shaft: Correlation between structure and mechanical response. Acta Biomater 2017; 48:270-288. [PMID: 27818305 DOI: 10.1016/j.actbio.2016.11.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Revised: 10/18/2016] [Accepted: 11/02/2016] [Indexed: 12/26/2022]
Abstract
Flight feathers are unique among a variety of keratinous appendages in that they are lightweight, stiff and strong. They are designed to withstand aerodynamic forces, but their morphology and structure have been oversimplified and thus understudied historically. Here we present an investigation of the shaft from seagull primary feathers, elucidate the hierarchical fibrous and porous structure along the shaft length, and correlate the tensile and nanomechanical properties to the fiber orientation. An analysis of the compressive behavior of the rachis based on a square-section model shows a good fit with experimental results, and demonstrates the synergy between the cortex and medulla. Flexural properties of the shaft along the shaft length, analyzed as a sandwich composite, reveal that although all flexural parameters decrease towards the distal shaft, the specific equivalent flexural modulus and strength increase by factors of 2 and 3, respectively. The failure mode in flexure for all specimens is buckling on the compressive surface, whereas the foamy medulla prevents destructive axial cracking and introduces important toughening mechanisms: crack deflection, fiber bridging, and microcracking. STATEMENT OF SIGNIFICANCE Using mechanics principles, we analyze the feather shaft as a composite beam and demonstrate that the flexural strength is extraordinary, considering its weight and tailored along the length. The cross section changes from circular in the proximal base to square/rectangular in the distal end. We also discovered that the composite design, a solid shell enclosing a foam core, produces synergistic strengthening and toughening to the feather at a minimum of weight.
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Affiliation(s)
- Bin Wang
- University of California, San Diego, La Jolla, CA 92093-0411, USA
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18
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Sarna M, Olchawa M, Zadlo A, Wnuk D, Sarna T. The nanomechanical role of melanin granules in the retinal pigment epithelium. Nanomedicine 2016; 13:801-807. [PMID: 27979745 DOI: 10.1016/j.nano.2016.11.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 11/09/2016] [Accepted: 11/29/2016] [Indexed: 11/16/2022]
Abstract
Nanomechanical properties of cells and tissues, in particular their elasticity, play an important role in different physiological and pathological processes. Recently, we have demonstrated that melanin granules dramatically modify nanomechanical properties of melanoma cells making them very stiff and, as a result, less aggressive. Although the mechanical effect of melanin granules was demonstrated in pathological cells, it was never studied in the case of normal cells. In this work, we analyzed the impact of melanin granules on nanomechanical properties of primary retinal pigment epithelium tissue fragments isolated from porcine eyes. The obtained results clearly show that melanin granules are responsible for the exceptional nanomechanical properties of the tissue. Our findings suggest that melanin granules in the retinal pigment epithelium may play an important role in sustaining the stiffness of this single cell layer, which functions as a natural mechanical barrier separating the retina from the choroid.
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Affiliation(s)
- Michal Sarna
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Poland; Laboratory of Imaging and Atomic Force Spectroscopy, Malopolska Centre of Biotechnology, Jagiellonian University, Poland.
| | - Magdalena Olchawa
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Poland
| | - Andrzej Zadlo
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Poland
| | - Dawid Wnuk
- Department of Cell Biology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Poland
| | - Tadeusz Sarna
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Poland
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El-Eskandrany MS, Al-Azmi A. Potential applications of cold sprayed Cu50Ti20Ni30 metallic glassy alloy powders for antibacterial protective coating in medical and food sectors. J Mech Behav Biomed Mater 2015; 56:183-194. [PMID: 26703232 DOI: 10.1016/j.jmbbm.2015.11.030] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 11/23/2015] [Accepted: 11/28/2015] [Indexed: 01/22/2023]
Abstract
Mechanical alloying was utilized for synthesizing of metallic glassy Cu50Ti20Ni30 alloy powders, using a low energy ball milling technique. The metallic glassy powders obtained after 100 h of ball milling had an average particle size of 1.7 mm in diameter and possessed excellent thermal stability, indexed by a relatively high glass transition temperature (358.3 °C) with a wide supercooled liquid region (61 °C). This amorphous phase crystallized into Ti2Cu and CuTiNi2 ordered phases through two overlapped crystallization temperatures at 419.3 °C and 447.5 °C, respectively. The total enthalpy change of crystallization was -4.8 kJ/mol. The glassy powders were employed as feedstock materials to double-face coating the surface of SUS 304 substrate, using cold spraying process under helium gas pressure at 400 °C. This coating material had an extraordinary high nanohardness value of 3.1 GPa. Moreover, it showed a high resistance to wear with a low value of the coefficient of friction ranging from 0.45 to 0.45. Biofilms were grown on 20-mm(2) SUS304 sheets coated coupons inoculated with 1.5 × 10(8) CFU ml(-1)E. coli. Significant biofilm inhibition (p The inhibition of biofilm formation by nanocrystalline powders of Cu-based provides a practical approach to achieve the inhibition of biofilms formation.
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Affiliation(s)
- M Sherif El-Eskandrany
- Nanotechnology and Advanced Materials Program, Energy and Building Research Center, Kuwait Institute for Scientific Research, Safat, 13109 Kuwait, State of Kuwait.
| | - Ahmed Al-Azmi
- Biotechnology Program, Environment and Life Sciences Research Center, Kuwait Institute for Scientific Research, Safat, 13109 Kuwait, State of Kuwait.
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Saeki K, Chin AF, Nonomura GT, Hilton JF, Chien YC, Marshall SJ, Marshall GW. In vitro evaluation of adhesive characteristics of 4-META/MMA-TBB resin with organic filler. Dent Mater 2015; 31:1567-78. [PMID: 26590030 DOI: 10.1016/j.dental.2015.10.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 05/19/2015] [Accepted: 10/13/2015] [Indexed: 11/21/2022]
Abstract
OBJECTIVES A commercial restorative material, BondfillSB (BF), is a modification of 4-META/MMA-TBB resin cement. BF uses a self-etching primer and added pre-polymerized organic fillers. We compared BF with another self-etching system, EasyBond (EB), in shear bond strength, bonded interface characteristics to human dentin and contraction gap when used in bulk-filling. METHODS Shear bond strength of BF and EB + Z100 (Z), bonded by different experience-level operators, was evaluated. Bonded interfaces were characterized by SEM, AFM, and AFM based nano-indentation. Contraction gaps (CG) at 0h and 24h after polymerization were evaluated for BF or EB bulk filled class I cavities. To meet the clinical recommendation, BF's powder was replaced by experimental radioopaque powder (BFO) for the CG study. EB was used with Z (EBZ) or with a resin marketed for bulk-fill base (SureFil-SDR-flow (EBSF)). RESULTS Shear bond strengths (Mean ± Standard Deviation (S.D.)) of BF (37.4 ± 2.6 MPa; n=36) were higher and less variable than EBZ (18.2 ± 7.6 MPa; n=36) (p<0.0001, One-way ANOVA). Weibull characteristic strength (η) differed significantly between materials (p<0.0001) but not between operators (p=0.90). EBZ often had non-uniform interfaces and a wider band of reduced elastic modulus (E) of greater than 20 μm across the interface. BF had uniform interfaces and a smaller width of affected dentin under the interface (∼1 μm). There was a difference in dentin-E between EBZ and BF up to 9 μm from the interface (mixed-effects model; P=0.03). A stratified linear regression model used for CG. EBSF and BFO showed significantly smaller CG than EBZ at time 0. None of three combinations showed any significant change between 0h-CG and 24h-CG. SIGNIFICANCE BF possessed bonding characteristics required to serve as a restorative.
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