Article
Chemistry, Multidisciplinary
Frederik Hegaard, Robert Biro, Koosha Ehtiati, Esben Thormann
Summary: In this study, the interactions between mobile ions and immobile charges within a sulfobetaine-based polyzwitterionic film were systematically investigated. The swelling behavior of the film in the presence of different salts was compared, and it was found that specific types of anions significantly influenced the swelling of the polycationic films. Furthermore, it was observed that the degree of swelling of the zwitterionic films depended on the anion type and increased with increasing ionic strength.
Article
Chemistry, Multidisciplinary
Ujjawal Bairagi, Josemon Jacob
Summary: A new stable and functional polyzwitterion was synthesized, showing bidirectional pH responsiveness and formation of dendritic fractal structures. Various elementary anions were successfully introduced into the hydrogels, demonstrating bidirectional swelling behavior. Anion release studies indicated high cumulative release rates for nitrate and phosphate anions, suggesting potential applications in agriculture and healthcare.
Article
Multidisciplinary Sciences
Chiao-Peng Hsu, Joydeb Mandal, Shivaprakash N. Ramakrishna, Nicholas D. Spencer, Lucio Isa
Summary: The study demonstrates that the relative contributions of friction, adhesion, and surface roughness in discontinuous shear thickening can be tuned in situ by modifying temperature, allowing the phenomenon to be switched on and off as needed. By characterizing at the single-colloid level, a more direct way to design smart non-Newtonian fluids is identified.
NATURE COMMUNICATIONS
(2021)
Article
Nanoscience & Nanotechnology
Monica G. Simoes, Georg Urstoeger, Robert Schennach, Ulrich Hirn
Summary: Adhesion occurs at nanoscale contact between surfaces, which can be evaluated using FRET spectroscopy/microscopy within a range of 1-10 nm. Increased pressure during film pressing leads to higher NSC and adhesion force/energy. FRET microscopy enables visualization of local variations in molecular contact.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Computer Science, Interdisciplinary Applications
Qing Yin, Yingxiao Liu, Ronaldo I. Borja
Summary: This paper proposed a scale-bridging technique to study the creep phenomena in shale at different scales and explored the creep mechanisms. Simulation results indicated that creep of the shale sample is mainly caused by viscoplastic deformation of the material, which is highly dependent on stress rate. Additionally, simulations of triaxial creep showed that the creep behavior of the shale sample is influenced by organics and clay constituents.
COMPUTERS AND GEOTECHNICS
(2021)
Article
Polymer Science
Apostolos Vagias, Andrew Nelson, Peixi Wang, Julija Reitenbach, Christina Geiger, Lucas Philipp Kreuzer, Thomas Saerbeck, Robert Cubitt, Edmondo Maria Benetti, Peter Mueller-Buschbaum
Summary: Time-of-flight neutron reflectometry (ToF-NR) reveals that polymer brushes made up of hydrophilic, cyclic macromolecules have a more compact conformation and lower roughness compared to linear brush analogues. This is because cyclic brushes do not have dangling chain ends extending at the polymer-vapor interface. Additionally, cyclic brushes have a larger swelling ratio and increased solvent uptake compared to linear brushes due to increased interchain steric repulsions. It is proposed that the differences in swelling ratios between linear and cyclic brushes are a result of entropic constraints.
MACROMOLECULAR RAPID COMMUNICATIONS
(2023)
Article
Engineering, Chemical
Bing Wu, Yunyun Sun
Summary: This study investigates the contact between two self-affine fractal surfaces, one being a rigid solid and the other a FCC deformable body. A normal contact model is established for the nanoscale interaction of these surfaces. The effects of surface morphology on contact force, atomic structure, and dislocation are examined. The results show that rougher surfaces result in larger negative forces due to the influence of surface morphology on interatomic interactions. The behavior of atomic structure change with normal displacement is monotonic, but the total dislocation lines length shows a non-monotonic variation due to phase transition caused by excessive atomic slip. The established model is compared with the classical micro-asperity model in terms of contact ratio-separation dependence.
Article
Multidisciplinary Sciences
Reinhard Hentschke, Jan Plagge
Summary: Current theoretical descriptions of rubber or elastomer friction are complex due to detailed mathematical models, but experimental coefficients of sliding friction show little structure, suggesting a simpler approach is possible. Through scaling and dimensional analysis, a relatively simple expression for the coefficient of friction is obtained, providing an intuitive understanding of the underlying physics and fitting experimental data for various conditions.
SCIENTIFIC REPORTS
(2021)
Article
Materials Science, Multidisciplinary
Liwei Sun, Lingjie Song, Xu Zhang, Shuaishuai Yuan, Shifang Luan
Summary: A hierarchical zwitterionic surface with bacterial phosphatase responsiveness was developed for preventing polymeric implant-associated bacterial infection. The surface showed self-adaptive bacterial responsiveness and biocompatibility, demonstrating great potential in combating infections.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Physics, Multidisciplinary
Natascha Hedrich, Kai Wagner, Oleksandr V. Pylypovskyi, Brendan J. Shields, Tobias Kosub, Denis D. Sheka, Denys Makarov, Patrick Maletinsky
Summary: The study demonstrated manipulation and interaction of antiferromagnetic domain walls using isolated 180 degree domain walls in a single crystal of Cr2O3, proposing a memory architecture based on topographically defined antiferromagnetic domain walls. These results advance the understanding of domain wall mechanics in antiferromagnets.
Article
Materials Science, Multidisciplinary
Shyamal Roy, Sonke Wille, Dan Mordehai, Cynthia A. Volkert
Summary: In this study, nanocontact plasticity in Au thin films was investigated using an atomic force microscope based indentation method. The results show the existence of distinct elastic and plastic regimes, and the measured dislocation densities are smaller than expected. Molecular dynamics simulations indicate that dislocation nucleation and glide alone cannot explain the low dislocation density, and increasing temperature accelerates thermally activated processes and reduces dislocation density.
Article
Mathematics, Interdisciplinary Applications
Robert L. Jackson, Yang Xu, Swarna Saha, Kyle D. Schulze
Summary: This study uses the boundary element method to predict the real contact area of perfectly elastic rough surfaces, aiming to confirm the linear relationship between contact area, root-mean-square slope, and applied load predicted by fractal diffusion-based rough surface contact theory. However, experimental results reveal a complex response that deviates from the expected behavior. Further evaluation of the variation in root-mean-square slope and system spectrum related to contact features is needed to understand why this discrepancy occurs in some types of surfaces and not others.
FRACTAL AND FRACTIONAL
(2021)
Article
Chemistry, Multidisciplinary
Sophia J. Bailey, Christopher W. Barney, Nairiti J. Sinha, Sai Venkatesh Pangali, Craig J. Hawker, Matthew E. Helgeson, Megan T. Valentine, Javier Read de Alaniz
Summary: An overlooked feature of Diels-Alder (DA) cycloadditions is the ability for DA adducts to undergo mechanically induced cycloreversion under force. In this study, mechanoresistant DA adducts were identified through computational design and used to enhance the failure strength of crosslinked hydrogels. Additionally, a cyclopentadiene derivative provided both mechanoresistant DA adducts and rapid gelation. Molecular-level design of DA crosslinks can improve the processing, mechanical durability, lifetime, and utility of biocompatible materials.
MATERIALS HORIZONS
(2022)
Article
Engineering, Mechanical
J. P. J. Truelove, D. A. Hills
Summary: The research compared the similarity in implied process zones based on violations of the plastic yield condition between different stress states. The results showed that strong agreement is unlikely to occur for realistic coefficients of friction. Therefore, analyzing the nucleation of fretting cracks as a form of crack branching/turning may be inappropriate, and the effect of normal load on crack nucleation is an important consideration.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Chemistry, Multidisciplinary
Christopher D. Cooper, Ian Addison-Smith, Horacio V. Guzman
Summary: Electrostatic interactions are critical for the assembly and stability of proteinaceous viral capsids. A generalized electrostatic model based on the Poisson-Boltzmann equation is developed to quantify the nanoscale electrostatic interactions between an AFM tip and a proteinaceous capsid. This method provides insights into the contribution of specific amino acids and atoms to the interaction force. The study also demonstrates the localized nature of the interaction between Zika capsid and AFM tips of different shapes.
Article
Radiology, Nuclear Medicine & Medical Imaging
Laura Beaton, Mairead Daly, Henry F. J. Tregidgo, Helen Grimes, Syed Moinuddin, Chris Stacey, Sami Znati, Julian Hague, Zainab A. Bascal, Paul E. Wilde, Sarah Cooper, Steven Bandula, Andrew L. Lewis, Matthew J. Clarkson, Ricky A. Sharma
Summary: This study evaluated the feasibility of using radiopaque beads as tumor substitutes for image-guided radiotherapy in liver tumor patients. The results showed that these beads were visible on imaging examinations, matched well with CBCT, and remained stable in position. This study is important for the research of liver tumor radiotherapy.
BRITISH JOURNAL OF RADIOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Evangelia Argentou, Carlos Amador, Anju Deepali Massey Brooker, Serafim Bakalis, Peter J. Fryer, Zhenyu Jason Zhang
Summary: The study reveals that low viscosity PDMS droplets can generate a uniform surface deposition profile, while high viscosity PDMS leads to localized deposition profile, which is related to the penetration behavior of oil droplets on cotton fabric. By optimizing the emulsion formulation, uniform surface deposition and excellent PDMS penetration profile can be achieved, maximizing tactile sensorial benefits.
Article
Pharmacology & Pharmacy
Andrew S. Mikhail, Michal Mauda-Havakuk, Ayele H. Negussie, Natalie Hong, Natalie M. Hawken, Camella J. Carlson, Joshua W. Owen, Olga Franco-Mahecha, Paul G. Wakim, Andrew L. Lewis, William F. Pritchard, John W. Karanian, Bradford J. Wood
Summary: Local administration of immunotherapy using drug-eluting embolic (DEE) microspheres can improve the effectiveness of immune modulators and reduce side effects. This study successfully loaded two immune modulators into radiopaque DEE microspheres and achieved controlled drug release.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2022)
Article
Radiology, Nuclear Medicine & Medical Imaging
Andrew S. Mikhail, William F. Pritchard, Ayele H. Negussie, Gazi Inkiyad, Dilara J. Long, Michal Mauda-Havakuk, Paul G. Wakim, William van der Sterren, Elliot B. Levy, Andrew L. Lewis, John W. Karanian, Bradford J. Wood
Summary: This study developed a model to estimate drug dose delivered to tumors after transarterial chemoembolization using radiopaque drug-eluting beads (DEBs) based on DEB density on cone-beam CT. The study also evaluated drug penetration into tissue in a woodchuck hepatoma model and found that DEB clusters had the greatest drug penetration.
INVESTIGATIVE RADIOLOGY
(2022)
Editorial Material
Physics, Multidisciplinary
Marie Hemingway, Mark Geoghegan
Article
Polymer Science
Alessandra Petroli, Mario Petroli, Marcello Romagnoli, Mark Geoghegan
Summary: This study utilizes a JKR formalism to extract the Young modulus, contact radius, and energy release rate from the retraction curve of a borosilicate glass colloidal probe from a PDMS surface using an atomic force microscope. The dependence of the energy release rate on crack speed is verified using a fracture mechanics-based method.
Article
Chemistry, Multidisciplinary
Adriana Sierra-Romero, Katarina Novakovic, Mark Geoghegan
Summary: This article evaluates the ongoing efforts to adapt adhesives towards achieving zero-waste living and suggests two promising solutions: the use of natural materials instead of petroleum-based polymers in conventional adhesives, and the production of dismantlable adhesives that can be debonded on demand. These approaches offer a new paradigm for zero-waste industrial production and consumer applications.
Article
Chemistry, Multidisciplinary
Robert E. Ducker, Oscar Siles Bruegge, Anthony J. H. M. Meijer, Graham J. Leggett
Summary: We demonstrate the mechanochemical regulation of a photochemical reaction using an atomic force microscope (AFM) probe to remove photocleavable nitrophenyl protecting groups from alkylsilane films. This process enables nanoscale differentiation of chemical reactivity with high spatial resolution. The study also shows that functionalization of nanolines with nitrilo triacetic acid allows for site-specific immobilization of histidine-tagged green fluorescent protein.
Article
Multidisciplinary Sciences
Ayele H. Negussie, Andrew S. Mikhail, Joshua W. Owen, Natalie Hong, Camella J. Carlson, Yiqing Tang, Kendal Paige Carrow, Michal Mauda-Havakuk, Andrew L. Lewis, John W. Karanian, William F. Pritchard, Bradford J. Wood
Summary: This study characterized the drug loading and release of TLR agonists and a checkpoint inhibitor from radiopaque embolic beads for potential use in the treatment of hepatocellular carcinoma. Different drugs exhibited different loading and release characteristics, potentially influenced by factors such as steric hindrance, hydrophobicity, and the electrostatic nature of the beads.
SCIENTIFIC REPORTS
(2022)
Article
Biochemistry & Molecular Biology
Alireza Meghdadi, Stephen A. Jones, Venisha A. Patel, Andrew L. Lewis, Timothy M. Millar, Dario Carugo
Summary: This study obtained a clinically relevant rheological model of sclerosing foams and correlated it with the foam's apparent viscosity, providing guidance for clinicians to select the most effective foam formulation.
Article
Polymer Science
Emma E. Brotherton, Edwin C. Johnson, Mark J. Smallridge, Deborah B. Hammond, Graham J. Leggett, Steven P. Armes
Summary: Surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) is used to polymerize a cis-diol-functional methacrylic monomer (GEO5MA) from planar silicon wafers. The hydrophilic PGEO5MA brush is selectively oxidized using sodium periodate to produce an aldehyde-functional hydrophilic PAGEO5MA brush. XPS analysis confirmed the successful oxidation and subsequent functionalization of the brushes. Moreover, protein adsorption was found to be minimal on the PGEO5MA brush-coated substrate, while strong protein adsorption occurred on the PAGEO5MA brush-coated substrate.
Correction
Multidisciplinary Sciences
Ayele H. Negussie, Andrew S. Mikhail, Joshua W. Owen, Natalie Hong, Camella J. Carlson, Yiqing Tang, Kendal Paige Carrow, Michal Mauda-Havakuk, Andrew L. Lewis, John W. Karanian, William F. Pritchard, Bradford J. Wood
SCIENTIFIC REPORTS
(2023)
Article
Chemistry, Multidisciplinary
Adriana Sierra-Romero, Katarina Novakovic, Mark Geoghegan
Summary: A reversible water-based electrostatic adhesive has been developed, with intermediate bond strength between pressure-sensitive and structural adhesives, suitable for large-scale recycling and dismantling.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Edwin C. Johnson, Spyridon Varlas, Oleta Norvilaite, Thomas J. Neal, Emma E. Brotherton, George Sanderson, Graham J. Leggett, Steven P. Armes
Summary: This study demonstrates the chemical adsorption of aldehyde-functional diblock copolymer spherical nanoparticles onto amine-functionalized surface-grafted polymer brushes via dynamic Schiff base chemistry. The aldehyde-functional brushes were treated with excess small-molecule diamine, and the resulting imine linkages were converted into secondary amine bonds via reductive amination. Friction force microscopy studies showed that the nanoparticles formed multiple dynamic imine bonds with the brushes, leading to a mean surface coverage of approximately 0.33, regardless of the nanoparticle size.
CHEMISTRY OF MATERIALS
(2023)
Review
Chemistry, Physical
Mark Geoghegan
Summary: This article reviews the experimental developments in the growth and application of surface-grafted weak polyelectrolytes, focusing on their surface, tribological, adhesive, and bioadhesive properties, as well as their role as actuators.
