Article
Multidisciplinary Sciences
Xingdong Sun, Wandi Wu, Renbo Zhang, Hongru Qu, Jie Wang, Ke Xu, Liangfei Fang, Liangyuan Xu, Rui Jiang
Summary: This study investigates the mechanical response and deformation mechanism of cortical bone material under complicated loading patterns. The research finds that bone fracture risk increases under compression-torsion coupling loads, and the reduction of anisotropy under compression load is a potential influencing factor. Comprehensive fracture patterns, including transverse and longitudinal fractures, are observed under coupling loads.
Article
Engineering, Environmental
Eunse Chang, Jinchuan Zhao, Chongxiang Zhao, Guangming Li, Patrick C. Lee, Chul B. Park
Summary: A new toughening strategy with nano-structured rubber inclusion is proposed in this study, which effectively enhances the toughness of polypropylene. By integrating vulcanization and in situ fibrillation processes, PP nanocomposites toughened with EPDM nano-fibrils are successfully fabricated, leading to unique properties and improved fracture behavior at a lower EPDM loading. The superior toughening efficiency of the crosslinked EPDM nanofibrillar network may be explained by a collective toughening mechanism involving multiple micro-scale mechanisms.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Construction & Building Technology
Shanshan Chen, Hao Wang, Junfeng Guan, Xianhua Yao, Lielie Li
Summary: A study on the effect of recycled coarse aggregate on recycled aggregate concrete specimens was conducted, proposing a concept of relative size and a simplified calculation equation for fictitious crack growth length. Fracture models were developed to determine tensile strength and fracture toughness of RAC at different curing ages, providing a linear relationship between peak load and fracture parameters for predicting peak load of large-scale structures.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Construction & Building Technology
Jianyou Lu, Zilong Zhou, Xinqing Chen, Peiyu Wang, Yichao Rui, Xin Cai
Summary: This study investigated the fracture mechanical properties and failure characteristics of rock-concrete interface at different ages. The experimental results showed that the fracture energy and fracture toughness of the interfaces increased with the age of concrete for granite, limestone, and marble. The growth rate was the highest between 2 and 3 days, but decreased significantly between 4 and 7 days. For the sandstone interface, the fracture toughness also increased with the increase of concrete age, but the fracture energy at 28 days was significantly lower than that at 7 days. Interestingly, when the age of concrete was 1 day, the fracture toughness and fracture energy of the interfaces were negatively correlated with the density of rock material.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Mechanics
Vitor Adriano, Robin Depraetere, Wim De Waele, Stijn Hertele
Summary: This study investigates the influence of porosity on crack sizing techniques in fracture toughness testing, showing that pores within workmanship criteria acceptable limits can lead to crack size errors exceeding validity limits set by testing standards.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Geochemistry & Geophysics
Fusheng Zha, Kai Huang, Bo Kang, Xianguo Sun, Jingwen Su, Yunfeng Li, Zhitang Lu
Summary: This paper investigated the effect of drying-wetting cycles on the mechanical properties and microstructural characteristics of red-bed argillaceous siltstone. The experimental results showed that the microstructure became less dense and uniform, and the porosity increased with the number of drying-wetting cycles. The stress-strain curve exhibited more pronounced nonlinearity and a longer compaction stage, while the uniaxial compression strength and elastic modulus decreased. Based on the evolution of dissipated energy, a new damage model was proposed and found to be in good agreement with the experimental data.
Article
Engineering, Environmental
Lei Zhou, Yacheng Jiang, Zheming Zhu, Bo Feng, Jianxing Chen, Haohan Wang
Summary: A series of freeze-thaw (FT) cycle experiments and drop-weight impact tests were conducted to investigate the dynamic fracture characteristics of fractured sandstone under FT cycles. The results showed that the dynamic elastic modulus and P/S wave velocities of sandstone decreased significantly after 10 cycles of FT. In addition, the porosity of sandstone increased with the number of FT cycles, and the crack growth velocity was positively correlated with the number of FT cycles.
COLD REGIONS SCIENCE AND TECHNOLOGY
(2023)
Article
Environmental Sciences
Kelly M. Dorgan, Sanjay R. Arwade
Summary: Infaunal organisms play a crucial role in mixing sediments through their burrowing activities. This study explores the role of sediment properties, specifically the cohesive properties, in resisting bioturbation. The results show that crack branching and tortuosity, as well as sediment mechanical properties, influence crack propagation paths. The findings suggest that material properties of sediments may be important in determining the extent of bioturbation.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2023)
Article
Nanoscience & Nanotechnology
Fei Chen, Ke Yan, Jianping Zhou, Yongsheng Zhu, Jun Hong
Summary: The incorporation of multilayer graphene and beta-Si3N4 whisker into porous Si3N4 ceramics can enhance their hardness and fracture toughness.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Correction
Physics, Multidisciplinary
A. N. Ponomarev, M. S. Barabashko, A. E. Rezvanova, E. P. Evtushenko
Summary: The article investigates the influence of porosity on the fracture toughness of hydroxyapatite/multi-walled carbon nanotubes biocomposite materials. The study reveals that changes in porosity significantly affect the fracture behavior of the materials.
RUSSIAN PHYSICS JOURNAL
(2021)
Article
Chemistry, Physical
M. Saravana Kumar, E. Mohan, S. Robinson, D. Thivya Prasad
Summary: Stir casting is important in producing Al-SiC10% composites, but challenges like achieving homogeneous distribution of SiC particles and low porosity persist. Additive Manufacturing (AM) technology overcomes these defects, as demonstrated in this study on AlSi10Mg parts manufactured using Laser-Powder Bed Fusion (LPBF). Results show AM samples have 14% less porosity, 28.6% higher tensile strength, 23.69% higher hardness, 50% higher fracture toughness, and 32.55% higher shear stress compared to SC samples. AM samples exhibit enhanced mechanical and morphological properties compared to conventional stir casting.
Article
Materials Science, Multidisciplinary
Satyapal Mahade, Abhilash Venkat, Nicholas Curry, Matthias Leitner, Shrikant Joshi
Summary: This study aims to evaluate the influence of different porosity levels on erosion behavior of APS processed YSZ TBCs, by producing TBCs with varying porosity levels using different spray powders, examining their microstructure through SEM analysis and evaluating their mechanical properties with micro-indentation technique, as well as conducting erosion tests. The correlation between microstructure, mechanical properties, and erosion performance was established, providing new insights for improving erosion resistance of APS deposited YSZ TBCs.
Article
Chemistry, Multidisciplinary
Eirini Tziviloglou, Zoi S. Metaxa, George Maistros, Stavros K. Kourkoulis, Dionysios S. Karousos, Evangelos P. Favvas, Nikolaos D. Alexopoulos
Summary: This investigation examines the potential of electrochemical impedance spectroscopy (EIS) in assessing the physical and structural properties of graphene-based cementitious nanocomposites. The study demonstrates that electrical resistivity decreases and total porosity increases with the inclusion of graphene nanoplatelets (xGnP). Moreover, there exists a linear correlation between fracture toughness and electrical resistivity, highlighting the usefulness of EIS in evaluating the physical and mechanical properties of conductive nano-reinforced cementitious nanocomposites.
Article
Engineering, Geological
Tielin Han, Zhihui Li, Yunsheng Chen
Summary: This study investigated the damage characteristics of sandstone cracks exposed to sodium sulfate attack under wet-dry cycles and quantitatively analyzed the degree of mechanical degradation. The results showed significant damage to the mechanical properties of sandstone under wet-dry cycles, with the greatest degradation in K-IC. Corresponding relationships were also found among the mechanical and physical properties, wet-dry cycle damage, and ion concentration.
INTERNATIONAL JOURNAL OF GEOMECHANICS
(2022)
Article
Materials Science, Multidisciplinary
Dong Wang, Kai Xu, Boxin Wei, Xiang Ding, Songlin Ran
Summary: Continuous tungsten fiber-reinforced tungsten-zirconium carbide-copper (W-f/W-ZrC-Cu) composites were prepared by infiltrating molten Zr14Cu51 and 40 wt.% Zr-Cu alloys into porous W-f/W + WC preforms. The composites showed high flexural strength and fracture toughness. The hybrid strengthening and toughening effects of continuous Wf and in situ-formed submicron-sized ZrC particles contributed to the superior combination properties of the composites.
Article
Endocrinology & Metabolism
Amy Creecy, Kyle L. Brown, Kristie L. Rose, Paul Voziyan, Jeffry S. Nyman
Summary: The research found that levels of deamidation of specific asparagine and glutamine residues in collagen I significantly increased with age, suggesting a new mechanism for the age-related reduction in fracture resistance of cortical bone.
Article
Endocrinology & Metabolism
Robert C. Singleton, George M. Pharr, Jeffry S. Nyman
Summary: The incidence of bone fractures increases with age due to declining bone quantity and quality. In males, the age-related decline in fracture toughness of cortical bone is characterized by increased stiffness and hardness with age, while viscoelasticity remains constant. The changes in tissue-level characteristics, such as mineralization, contribute to decreased fracture toughness in male cortical bone.
Article
Biophysics
Gregory B. Lowen, Katherine A. Garrett, Stephanie N. Moore-Lotridge, Sasidhar Uppuganti, Scott A. Guelcher, Jonathan G. Schoenecker, Jeffry S. Nyman
Summary: Delayed long bone fracture healing and nonunion are significant socioeconomic burdens. Mechanical stimulation plays a crucial role in bone repair process. Understanding the impact of interfragmentary strain (IFS) in terms of its magnitude, mode, and commencement on fracture healing can guide the development of new therapeutic strategies. This proof-of-concept finite element analysis study focuses on identifying the design parameters of intramedullary nails (IMNs) that have the largest impact on IFS in a murine transverse femoral osteotomy model. Results show that the nail material, distance between interlocking screws, and clearance between the nail and endosteal surface are important factors affecting IFS. Therefore, low modulus IMNs, such as PEEK, can be used alongside commercially available SS nails to investigate the effect of initial IFS or stability on fracture healing in different biological repair conditions.
JOURNAL OF BIOMECHANICAL ENGINEERING-TRANSACTIONS OF THE ASME
(2022)
Article
Endocrinology & Metabolism
M. Saito, S. N. Moore-Lotridge, S. Uppuganti, S. Egawa, T. Yoshii, J. P. Robinette, S. L. Posey, B. H. Y. Gibson, H. A. Cole, G. D. Hawley, S. A. Guelcher, S. B. Tanner, J. R. McCarthy, J. S. Nyman, J. G. Schoenecker
Summary: This study found that bisphosphonates can prevent severe injury-induced bone loss and soft tissue calcification if administered early after injury, without interfering with bone repair or remodeling.
OSTEOPOROSIS INTERNATIONAL
(2022)
Article
Cardiac & Cardiovascular Systems
J. Ethan Joll Ii, Matthew R. Bersi, Jeffry S. Nyman, W. David Merryman
Summary: Postmenopausal women with severe osteoporosis tend to have worse cardiovascular outcomes. This study evaluated the left ventricle and aortic valve phenotype of ovariectomized mice on a Western diet. The results showed that ovariectomized mice had increased left ventricle mass compared to control mice, but no fibrosis. This model provides a novel method for studying left ventricle hypertrophy in female populations.
AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY
(2022)
Article
Instruments & Instrumentation
Donald H. Lee, Kaitlyn Reasoner, Sasidhar Uppuganti, Mihir J. Desai, Jeffry S. Nyman
Summary: This study investigated the safety and utility of impact microindentation technique in measuring bone quality during surgical procedures. The results showed that there were no significant differences in bone material strength index (BMSi) between patients with different fracture histories, indicating that BMSi may not be sensitive to osteoporosis. The study demonstrated the feasibility of intraoperative impact microindentation but called for further research to determine its ability to identify patients with inferior bone matrix quality.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2022)
Article
Endocrinology & Metabolism
Sasidhar Uppuganti, Thammathida Ketsiri, Yumeng Zhang, Mark D. Does, Jeffry S. Nyman
Summary: This study found that HR-pQCT parameters are capable of predicting the bending strength of cortical bone, with cortical area and estimated failure load showing the strongest correlation with ultimate moment. However, there was no significant correlation between HR-pQCT parameters and post-yield displacement, an indicator of bone brittleness.
Article
Computer Science, Interdisciplinary Applications
Thammathida Ketsiri, Sasidhar Uppuganti, Kevin D. Harkins, Daniel F. Gochberg, Jeffry S. Nyman, Mark D. Does
Summary: Ultrashort echo time (UTE) MRI techniques can be used to assess the concentration of water in bones, which have the potential to serve as biomarkers for bone fracture risk. This study demonstrates that MRI-derived measures of collagen-bound water concentration (C-bw) and pore water concentration (C-pw) improve the prediction of bone mechanical properties and have the potential to assess patient-specific bone fragility risk.
COMPUTER METHODS IN BIOMECHANICS AND BIOMEDICAL ENGINEERING
(2023)
Article
Endocrinology & Metabolism
Rafay Ahmed, Sasidhar Uppuganti, Shrey Derasari, Joshua Meyer, Jacquelyn S. Pennings, Florent Elefteriou, Jeffry S. Nyman
Summary: This study assessed the ability of matrix-sensitive techniques to differentiate between NF1 mice and wild-type mice. The results showed that low bound water and cortical volumetric bone mineral density were the most accurate characteristics for distinguishing between the two genotypes in femurs, while cyclic reference point indentation tests' average unloading slope was the most sensitive in differentiating tibias. These findings provide guidance for the clinical trials of NF1.
JOURNAL OF BONE AND MINERAL RESEARCH
(2022)
Article
Cardiac & Cardiovascular Systems
J. Ethan Joll, Lance A. Riley, Matthew R. Bersi, Jeffry S. Nyman, W. David Merryman
Summary: This study demonstrates that genetic ablation of the Sost gene can prevent aortic valve stenosis in aged mice on a Western diet. This reveals a novel role for sclerostin in the cardiovascular system. It is one of the first studies to directly manipulate sclerostin in a cardiovascular disease model, specifically studying the aortic valve. Additionally, this study highlights the potential involvement of Hox genes in cardiovascular disease, with the upregulation of pan-Hox genes in the aortic roots of sclerostin knockouts.
AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY
(2022)
Review
Endocrinology & Metabolism
Thomas L. Willett, Paul Voziyan, Jeffry S. Nyman
Summary: The accumulation of advanced glycation end-products (AGEs) in bone may increase fracture risk, but there is a lack of clinical trials demonstrating the effectiveness of inhibiting AGE accumulation in preventing fractures. Further research is needed to understand the different types of AGEs in the bone extracellular matrix and their specific contributions to hindering fracture resistance, in order to develop strategies for preventing fragility fractures.
Article
Engineering, Biomedical
Mustafa Unal, Sasidhar Uppuganti, Daniel Y. Dapaah, Rafay Ahmed, Jacquelyn S. Pennings, Thomas L. Willett, Paul Voziyan, Jeffry S. Nyman
Summary: Raman spectroscopy (RS) can detect the accumulation of advanced glycation end-products (AGEs) and measure matrix-sensitive properties related to the fracture toughness of human cortical bone. However, it is unclear if the sugar-mediated accumulation of AGEs affects the fracture toughness of human cortical bone as indicated by the negative correlations between amide I sub-peak ratios.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2023)
Article
Spectroscopy
Rekha Gautam, Rafay Ahmed, Ezekiel Haugen, Mustafa Unal, Sean Fitzgerald, Sasidhar Uppuganti, Anita Mahadevan-Jansen, Jeffry S. Nyman
Summary: This study investigated the feasibility of using spatially offset Raman spectroscopy (SORS) to acquire Raman bands related to bone fracture resistance. The results showed that autoclaving of femur mid-shafts reduced the yield stress of cortical beams. Autoclaving also affected the Raman characteristics of the organic matrix, but changes in Raman properties related to bone strength could still be detected with SORS.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2023)
Article
Chemistry, Analytical
Rafay Ahmed, Mustafa Unal, Rekha Gautam, Sasidhar Uppuganti, Shrey Derasari, Anita Mahadevan-Jansen, Jeffry S. Nyman
Summary: The fracture resistance of bone is determined by the hierarchical arrangement of minerals, collagen fibrils, non-collagenous proteins, and water. Raman spectroscopy can detect changes in the protein structure and composition, making it a valuable tool for studying bone properties.
Review
Chemistry, Analytical
Mustafa Unal, Rafay Ahmed, Anita Mahadevan-Jansen, Jeffry S. Nyman
Summary: Raman spectroscopy is a non-destructive method used to analyze the physiochemical properties of bone. Over two decades of research have developed multiple methods for acquiring Raman signals from bone and determining peak ratios, although selecting which methods to use is not always clear. This article provides guidance on how RS instruments influence Raman spectra quality and the challenges in preparing acquired spectra for determining bone matrix properties.