Anisotropic NMR parameters, such as residual dipolar couplings (RDCs), residual chemical shift anisotropies (RCSAs) and residual quadrupolar couplings (RQCs or Δν ), appear in solution-state NMR when the molecules under study are subjected to a degree of order. The tunable alignment by reversible compression/relaxation of gels (PMMA and p-HEMA) is an easy, user-friendly, and very affordable method to measure them. When using this method, a fraction of isotropic NMR signals is observed in the NMR spectra, even at a maximum degree of compression. To explain the origin of these isotropic signals we decided to investigate their physical location inside the NMR tube using deuterium 1D imaging and MRI micro-imaging experiments. It was observed that after a certain degree of compression the gels start to buckle and they generate pockets of isotropic solvent, which are never eliminated. The amount of buckling depends on the amount of cross-linker and the length of the gel.
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http://dx.doi.org/10.1002/chem.201603333 | DOI Listing |
Sci Rep
January 2025
The Fourth Engineering Co., LTD, China Railway Fourth Bureau, Hefei, 230012, People's Republic of China.
Research investigating the complex mechanical properties and energy evolution mechanisms of frozen calcareous clay under the influence of multiple factors is crucial for optimizing the artificial ground freezing method in shaft sinking, thereby enhancing construction quality and safety. In this study, a four-factor, four-level orthogonal test was devised, taking into account temperature, confining pressure, dry density, and water content. The complex nonlinear curvilinear relationship between deviatoric stress, volume strain, and axial strain of frozen calcareous clay under different interaction levels was analyzed.
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January 2025
College of Civil Engineering, Guizhou University, Huaxi District, Guiyang, 550025, Guizhou, China.
Long-term erosion by acidic solutions in karst regions leads to continuous deterioration of the physical and mechanical properties at the interfaces of engineering structures, adversely affecting their operational performance. To investigate the degradation patterns of the mechanical properties and corrosion mechanisms of the concrete‒limestone composite (CLC) after exposure to acidic corrosion, three kinds of CLC samples treated with acidic solutions of different pH values were fabricated. Mechanical property analysis was conducted via triaxial compression testing methods.
View Article and Find Full Text PDFTissue Eng Part A
January 2025
C. Wayne McIlwraith Translational Medicine Institute, Colorado State University, Fort Collins, Colorado, USA.
Scaffolds made from cartilage extracellular matrix are promising materials for articular cartilage repair, attributed to their intrinsic bioactivity that may promote chondrogenesis. While several cartilage matrix-based scaffolds have supported chondrogenesis and/or , it remains a challenge to balance the biological response (e.g.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences, Suzhou 215123, China.
In the study of GaN/AlGaN heterostructure thermal transport, the interference of strain on carriers cannot be ignored. Although existing research has mainly focused on the intrinsic electronic and phonon behavior of the materials, there is a lack of studies on the transport characteristics of the electron-phonon coupling in heterostructures under strain control. This research comprehensively applies first-principles calculations and the Boltzmann transport equation simulation method to deeply analyze the thermal transport mechanism of the GaN/AlGaN heterojunction considering in-plane strain, with particular attention to the regulatory role of electron-phonon coupling on thermal transport.
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March 2025
Blue Mountains World Interdisciplinary Innovation Institute (bmwi3), Blue Mountains, New South Wales, Australia.
Here, we report on the first part of a two-part experimental series to elucidate spatiotemporal cytoskeletal remodeling, which underpins the evolution of stem cell shape and fate, and the emergence of tissue structure and function. In Part I of these studies, we first develop protocols to stabilize microtubules exogenously using paclitaxel (PAX) in a standardized model murine embryonic stem cell line (C3H/10T1/2) to maximize comparability with previously published studies. We then probe native and microtubule-stabilized stem cells' capacity to adapt to volume changing stresses effected by seeding at increasing cell densities, which emulates local compression and tissue template formation during development.
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