An Al₂O₃/5 vol%·ZrO₂/5 vol%·Y₃Al₅O (YAG) tri-phase composite was manufactured by surface modification of an alumina powder with inorganic precursors of the second phases. The bulk materials were produced by die-pressing and pressureless sintering at 1500 °C, obtaining fully dense, homogenous samples, with ultra-fine ZrO₂ and YAG grains dispersed in a sub-micronic alumina matrix. The high temperature mechanical properties were investigated by four-point bending tests up to 1500 °C, and the grain size stability was assessed by observing the microstructural evolution of the samples heat treated up to 1700 °C. Dynamic indentation measures were performed on as-sintered and heat-treated Al₂O₃/ZrO₂/YAG samples in order to evaluate the micro-hardness and elastic modulus as a function of re-heating temperature. The high temperature bending tests highlighted a transition from brittle to plastic behavior comprised between 1350 and 1400 °C and a considerable flexural strength reduction at temperatures higher than 1400 °C; moreover, the microstructural investigations carried out on the re-heated samples showed a very limited grain growth up to 1650 °C.
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http://dx.doi.org/10.3390/ma8020611 | DOI Listing |
Comput Struct Biotechnol J
December 2024
Department of Population and Quantitative Health Sciences, Case Western Reserve University, 2109 Adelbert Rd, Cleveland, 44106, OH, USA.
Due to the development of next-generation sequencing technology and an increased appreciation of their role in modulating host immunity and their potential as therapeutic agents, the human microbiome has emerged as a key area of interest in various biological investigations of human health and disease. However, microbiome data present a number of statistical challenges not addressed by existing methods, such as the varying sequencing depth, the compositionality, and zero inflation. Solutions like scaling and transformation methods help to mitigate heterogeneity and release constraints, but often introduce biases and yield inconsistent results on the same data.
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February 2024
National Institute on Aging, Baltimore, MD, USA.
Adv Sci (Weinh)
April 2024
Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
Materials with high stretchability and conductivity are used to fabricate stretchable electronics. Self-healing capability and four-dimensional (4D) printability are becoming increasingly important for these materials to facilitate their recovery from damage and endow them with stimuli-response properties. However, it remains challenging to design a single material that combines these four strengths.
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June 2023
Department of Health Promotion and Community Health, Faculty of Health Sciences, American University of Beirut, Beirut, Lebanon.
Background: Tobacco use remains the leading cause of preventable disease, disability, and death in the world. Lebanon has an exceptionally high tobacco use burden. The World Health Organization endorses smoking cessation advice integrated into primary care settings as well as easily accessible and free phone-based counseling and low-cost pharmacotherapy as standard of practice for population-level tobacco dependence treatment.
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September 2022
From the Division of Neuroradiology, Department of Radiology (R.K., M.K., A.B., Y.O., A.A.C., E.L., A.S., T.M.) and Department of Pathology (E.P., S.C.P.), Michigan Medicine, University of Michigan, 1500 E Medical Center Dr, UH B2, Ann Arbor, MI 48109; and Department of Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan (R.K., M.K.).
The World Health Organization (WHO) published the fifth edition of the (WHO CNS5) in 2021, as an update of the WHO central nervous system (CNS) classification system published in 2016. WHO CNS5 was drafted on the basis of recommendations from the Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy (cIMPACT-NOW) and expounds the classification scheme of the previous edition, which emphasized the importance of genetic and molecular changes in the characteristics of CNS tumors. Multiple newly recognized tumor types, including those for which there is limited knowledge regarding neuroimaging features, are detailed in WHO CNS5.
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