Biomechanical tests of human femora have shown that small variations of the loading direction result in significant changes in measured bone mechanical properties. However, the heterogeneity in geometrical and bone tissue properties does not make human bones well suited to reproducibly assess the effects of loading direction on stiffness and strength. To precisely quantify the influence of loading direction on stiffness and strength of femora loaded at the femoral head, we tested femora from C57BL/6 inbred mice. We developed an image-based alignment protocol and investigated the loading direction influence on proximal femur stiffness and strength. An aluminum femoral phantom and C57BL/6 femora were tested under compression with different loading directions. Both tests, with the aluminum phantom and the murine bones, showed and quantified the linear dependence of stiffness on loading direction: a 5 degrees change in loading direction resulted in almost 30% change in stiffness. Murine bone testing also revealed and quantified the variation in strength due to loading direction: 5 degrees change in loading direction resulted in 8.5% change in strength. In conclusion, this study quantified, for the first time, the influence of misalignment on bone stiffness and strength for femoral head loading. We showed the extreme sensitivity of this site regarding loading direction.
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http://dx.doi.org/10.1515/BMT.2008.019 | DOI Listing |
Eur J Nucl Med Mol Imaging
January 2025
Department of Hepatobiliary Surgery and Liver Transplantation Center, The Fifth Affiliated Hospital of Sun Yat-Sen University, 52 Mei Hua East Road, Zhuhai, 519000, China.
Purpose: Cancer-associated fibroblasts (CAFs) are the primary stromal component of the tumor microenvironment in hepatocellular carcinoma (HCC), affecting tumor progression and post-resection recurrence. Fibroblast activation protein (FAP) is a key biomarker of CAFs. However, there is limited evidence on using FAP as a target in near-infrared (NIR) fluorescence imaging for HCC.
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January 2025
Institute of Nano Science and Technology (INST), Sector-81, Mohali, Punjab 140306, India.
Tuberculosis (TB) triggers a robust immune response, which leads to significant destruction of the lung tissue at the site of infection, aiding in the transmission of (Mtb) to the hosts. The excessive inflammatory response contributes heavily to extracellular matrix (ECM) damage, which is linked to high mortality rates among TB patients. Matrix metalloproteinases (MMPs), particularly MMP-2 and MMP-9, are pivotal in the breakdown of the ECM, worsening tissue destruction.
View Article and Find Full Text PDFNature
January 2025
Department of Chemical Engineering, University College London, London, UK.
Methane, the major component of natural and shale gas, is a significant carbon source for chemical synthesis. The direct partial oxidation of methane to liquid oxygenates under mild conditions is an attractive pathway, but the molecule's inertness makes it challenging to achieve simultaneously high conversion and high selectivity towards a single target product. This difficulty is amplified when aiming for more valuable products that require C-C coupling.
View Article and Find Full Text PDFEnviron Toxicol Chem
January 2025
Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University, Nonoichi, Ishikawa, 921-8836 Japan.
Polymer-coated fertilizers, widely used in rice cultivation in Japan, contribute to reactive nitrogen management and agricultural productivity but are a source of microplastics in the environment. Here, we investigated microplastics derived from polymer-coated fertilizer (microcapsule) runoff in Japanese paddy fields at 38 sites to quantitatively assess the behavior of microcapsules in paddy fields, and to estimate the total amount of runoff and accumulation in Japan. We also examined the factors causing variations in the amount of runoff among paddy fields.
View Article and Find Full Text PDFPNAS Nexus
January 2025
Thrust of Earth, Ocean and Atmospheric Sciences Function Hub, The Hong Kong University of Science and Technology (Guangzhou), Guangzhou 511453, China.
Modulating the electronic structure of noble metals via electronic metal-support interaction (EMSI) has been proven effectively for facilitating molecular oxygen activation and catalytic oxidation reactions. Nevertheless, the investigation of the fundamental mechanisms underlying activity enhancement has primarily focused on metal oxides as supports, especially in the catalytic degradation of volatile organic compounds. In this study, a novel Pt catalyst supported on nitrogen-doped carbon encapsulating FeNi alloy, featuring ultrafine Pt nanoparticles, was synthesized.
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