17 research outputs found

    Laser powder bed fusion of high-strength and corrosion-resistant Inconel alloy 725

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    The development of additive manufacturing, or three-dimensional (3D) printing, technologies has produced breakthroughs in the design and manufacturing of products by enhancing design freedom and minimising manufacturing steps. In addition, the complex, unique microstructures imparted by the additive processes offer prospects of unprecedented advances to produce high-performance metal alloys for high-temperature and corrosive environments. Here, we present the first additive manufacturing of Inconel alloy 725, an advanced nickel-base superalloy that is the widely accepted gold standard material of choice for oil and gas, chemical, and marine applications. We explore the printability of Inconel alloy 725 and identify a wide processing space to build material with a crack- and near-pore-free microstructure. The conventionally heat-treated Inconel alloy 725 has an equiaxed, near-fully recrystallised microstructure containing copious twin boundaries and nano-precipitates. It also displays promising tensile properties and corrosion resistance compared to its wrought counterpart. Our work opens the door toward additive manufacturing of Inconel alloy 725 components with optimised microstructure and topology geometry for applications in harsh environments

    Clinical Implication of Targeting of Cancer Stem Cells

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    The existence of cancer stem cells (CSCs) is receiving increasing interest particularly due to its potential ability to enter clinical routine. Rapid advances in the CSC field have provided evidence for the development of more reliable anticancer therapies in the future. CSCs typically only constitute a small fraction of the total tumor burden; however, they harbor self-renewal capacity and appear to be relatively resistant to conventional therapies. Recent therapeutic approaches aim to eliminate or differentiate CSCs or to disrupt the niches in which they reside. Better understanding of the biological characteristics of CSCs as well as improved preclinical and clinical trials targeting CSCs may revolutionize the treatment of many cancers. Copyright (c) 2012 S. Karger AG, Base

    Effect of ultrasonic melt treatment on intermetallic phase formation in a manganese-modified Al-17Si-2Fe alloy

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    Hypereutectic Al-Si based alloys are important automotive materials. Both manganese (Mn) addition and ultrasonic melt treatment (USMT) have each proved to be effective in modifying the embrittling platelet-like δ-Al FeSi and β-Al FeSi intermetallic compounds (IMCs) in these alloys. However, previous studies have identified no clear synergy in combining Mn addition with USMT to control these IMCs. This work presents a systematic study of the individual and combined effects of different levels of Mn addition and USMT on the formation of Fe-containing IMCs in an Al-17Si-2Fe alloy. Increasing the Mn content without USMT resulted in macro-segregation and formation of coarse IMCs. In addition, not all δ-Al FeSi /β-Al FeSi IMCs transformed into the desirable α-Al (Fe,Mn) Si IMC. In contrast, the combination of USMT and Mn addition avoided all these issues. The resultant microstructure was featured by fine dispersed polyhedral α-Al (Fe,Mn) Si phase particles. The volume fraction of the IMCs was quantified and compared with predictions made from the Scheil equation and the equilibrium lever rule. In the absence of USMT, neither the Scheil equation nor the lever rule method offered reasonable predictions. Conversely, the measured volume fraction of the Fe-containing IMCs with USMT closely agreed with the lever rule predictions. The underlining mechanisms for the effect of Mn and USMT on Fe-containing IMC formation and the effect of USMT alone on the Fe-containing IMC selection were discussed and proposed

    Integrating ancillary studies in a large clinical trial: The design and rationale of the APEX library

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    Copyright © 2008 Elsevier B.V. All rights reserved. ScienceDirect® is a registered trademark of Elsevier B.V.The APEX library was a coordinated and integrated set of ancillary analyses and substudies that were a part of the large APEX-AMI trial. The library included electrocardiogram, angiographic, blood biomarker, genetics, and MRI components. Operationally, the goals and administration of the APEX library were developed concurrently with the design of the parent trial. The goal recruitment in the library was met due to this approach. These data will provide important insights into the pathobiology of acute myocardial infarction and the relationships between inflammation, thrombosis, genetics, and classic clinical markers from angiograms, electrocardiograms, and patient demographics. In conclusion, the APEX library is an example of successful collaboration among academic trial leaders, site investigators, and pharmaceutical sponsors. The operational paradigm of this effort should be considered in future investigations so that important advances in clinical care of disease can be realized efficiently.Kenneth W. Mahaffey, Craig J. Reist, Yuling Fu, Sorin J. Brener, Pierre Theroux, Manesh R. Patel, Amanda Stebbins, Cynthia M. Westerhout, Thomas G. Todaro, Peter X. Adams, Christopher B. Granger, Paul W. Armstrong, on behalf of the APEX Library Study Investigator

    Efeitos do sexo, do grupo racial e da idade ao abate nas características de carcaça e maciez da carne de caprinos Carcass and meat tenderness of goats according to age, breed group and age at slaughter

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    Este trabalho foi realizado com os objetivos de quantificar e qualificar a carcaça e os cortes cárneos de cabritos de dois sexos (machos e fêmeas) e três grupos raciais - Alpino; ½ Boer + ½ Alpino (½ BA); e ¾ Boer + ¼ Alpino (¾ BA) - abatidos em três idades (aos 60, 90 e 120 dias de confinamento), visando avaliar o aproveitamento de cabritos provenientes de rebanhos leiteiros. As carcaças foram avaliadas pelas características de peso, rendimento, conformação, gordura de cobertura, comprimento interno e externo, comprimento da perna, perímetro da garupa, profundidade torácica, largura da garupa, compacidade, rendimento dos cortes cárneos e proporção dos tecidos. Os dados foram analisados em delineamento inteiramente casualizado, em esquema fatorial incompleto 2 X 3 X 3 (2 sexos X 3 grupos raciais X 3 idades de abate). O aumento da idade dos animais promove aumento do peso e das medidas da carcaça, assim como dos componentes comestíveis da carcaça e do rendimento comercial. Mestiços Boer apresentam maior compacidade de perna e menos osso em relação aos Alpinos. O grupo racial, a idade de abate e o sexo não influenciam a maciez da carne.<br>The objective of this experiment was to evaluate the yield and quality of the carcass and meat cuts from kids of both sexes, slaughtered at three different ages, aiming to use animals from dairy herds. Forty-one kids were used, from three breed groups: Alpine, ½ Boer ½ Alpine (½ BA) and ¾ Boer ¼ Alpine (¾ BA), which were slaughtered at 60, 90 or 120 days of slaughter age. The animals were raised in a feedlot system. The following carcass traits were evaluated: carcass weight, commercial yield, conformation, subcutaneous fat, internal and external length, leg length, rump perimeter, thoracic depth, rump width, compactness, meat cut yield and tissue proportion. Meat tenderness was evaluated by means of the Warner-Bratzler shear force. Data were analyzed as an incomplete factorial arrangement (2 sexes X 3 breed groups X 3 slaughter ages), in a complete randomized design. As age increased, so did carcass weight and characteristics, as well as the weight of edible carcass components and commercial yield. The Boer crossbreds showed higher leg compactness and less bone compared to the Alpines. No difference in meat tenderness was observed for breed group, age or sex
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