In the present work, constitutive models for densification and grain growth were employed to investigate the sintering behavior of pure hydroxyapatite ceramics. For densification study, lattice diffusion, grain-boundary diffusion, and interface reaction mechanisms, and for grain-growth study, surface diffusion mechanism, were considered respectively. Hydroxyapatite ceramics were pressurelessly sintered. The sintering results were discussed and compared with the modeling results. Based on the constitutive models employed and the experimental results obtained, grain-boundary diffusion was identified as the dominant mechanism for the densification of the investigated hydroxyapatite. The grain-growth model provided a good prediction to the grain growth of the investigated hydroxyapatite. The activation energies for densification and grain growth of hydroxyapatite ceramics were evaluated as 1150+/-40 and 1020+/-40 KJ mol(-1), respectively.
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http://dx.doi.org/10.1016/j.biomaterials.2004.05.027 | DOI Listing |
Curr Microbiol
January 2025
State Key Laboratory of Developmental Biology of Freshwater Fish, Engineering Research Center of Polyploidy Fish Reproduction and Breeding of the State Education Ministry, College of Life Science, Hunan Normal University, Changsha, 410081, People's Republic of China.
Gut mucosal immunity of teleost is mainly governed by mucosa-associated lymphoid tissues (MALT) and indigenous microbiota on mucosal surfaces of gut tract, which can confer protection against pathogenic invasion. However, the probiotic features of bacterial isolates from gut tract of triploid cyprinid fish (TCF) were largely unclear. In this study, Lysinibacillus and Enterobacter strains were isolated for probiotic identification.
View Article and Find Full Text PDFPlant Biol (Stuttg)
January 2025
Laboratório de Ecologia Vegetal, Departamento de Biologia Geral, Universidade Estadual de Montes Claros, Montes Claros, Minas Gerais, Brazil.
The success of pollen-pistil interaction in Mauritia flexuosa (buriti), a palm adapted to the humid ecosystems, 'veredas', within the Cerrado, is influenced by intrinsic and environmental factors. Its supra-annual flowering, dioecy, and adverse climate conditions pose challenges for fertilization, therefore information on floral biology is essential. This study aimed to ascertain stigma receptivity, and elucidate structural, cytochemical, and ultrastructural aspects of the pollen-pistil relationship.
View Article and Find Full Text PDFBMC Plant Biol
January 2025
Field Crops Research Institute, Agricultural Research Center, Giza, 12619, Egypt.
Studying genetic variability through the phenotypic performance of genotypes is crucial in the breeding program. Therefore, evaluating both yield performance and stability across diverse environments is essential in yield trials to identify high-yield potential and stable cultivars. In this study, we employed 12 univariate and 10 multivariate stability models to analyze how genotype (G), environment (E), and their interaction (G × E) affect the yield performance of 32 barley genotypes across 10 environments.
View Article and Find Full Text PDFMol Biol Rep
January 2025
Plant Protection and Bimolecular Diagnosis Department, Arid Lands Cultivation Research Institute, City of Scientific Research and Technological Applications, New Borg El-Arab 21934, Alexandria, Egypt.
Background: Heavy metal contamination, particularly from lead (Pb), poses a significant threat to plant agriculture worldwide, adversely affecting growth, physiological functions, and yield. Signalling molecules such as calcium and salicylic acid are known to mitigate various stresses in plants, prompting this study to explore their interaction with Pb stress in wheat.
Methods: A pot experiment was conducted in which wheat grains were primed with either distilled water, 5 mM calcium (Ca), or 0.
PLoS One
January 2025
Faculty of Science and Engineering, Waseda University, Tokyo, Japan.
Gold (or electrum) in hydrothermal fluid precipitates directly from gold sulfide complex and/or partly via suspended nanoparticles. The hydrothermal fluid contains "invisible gold" that is atomically dispersed in sulfide minerals or as nanoparticles with a size of less than 10 nm. However, the contribution of these gold nanoparticles to the formation of native gold and its alloy with silver (electrum) remains unclear.
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