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Transient Electronics: Thermally Triggered Degradation of Transient Electronic Devices (Adv. Mater. 25/2015) 下载免费PDF全文
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Olivia M. Guillin Caroline Vindry Thophile Ohlmann Laurent Chavatte 《International journal of molecular sciences》2022,23(3)
The infection of CD4 T-lymphocytes with human immunodeficiency virus (HIV), the etiological agent of acquired immunodeficiency syndrome (AIDS), disrupts cellular homeostasis, increases oxidative stress and interferes with micronutrient metabolism. Viral replication simultaneously increases the demand for micronutrients and causes their loss, as for selenium (Se). In HIV-infected patients, selenium deficiency was associated with a lower CD4 T-cell count and a shorter life expectancy. Selenium has an important role in antioxidant defense, redox signaling and redox homeostasis, and most of these biological activities are mediated by its incorporation in an essential family of redox enzymes, namely the selenoproteins. Here, we have investigated how selenium and selenoproteins interplay with HIV infection in different cellular models of human CD4 T lymphocytes derived from established cell lines (Jurkat and SupT1) and isolated primary CD4 T cells. First, we characterized the expression of the selenoproteome in various human T-cell models and found it tightly regulated by the selenium level of the culture media, which was in agreement with reports from non-immune cells. Then, we showed that selenium had no significant effect on HIV-1 protein production nor on infectivity, but slightly reduced the percentage of infected cells in a Jurkat cell line and isolated primary CD4 T cells. Finally, in response to HIV-1 infection, the selenoproteome was slightly altered. 相似文献
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Eva Olivia Leontien Lantsoght Rutger T. Koekkoek Dick Hordijk Ane de Boer 《Structure and Infrastructure Engineering》2018,14(3):365-380
Proof load tests of bridges can be very useful for structures with a lack of information, or for structures of which the effect of material degradation is difficult to assess. Contrary to diagnostic load testing, proof load testing is not well-defined in current standards in terms of required load and analysis of measurements. The risk related to the high loads used in proof load testing requires standardisation for these tests. The paper highlights important considerations for proof load testing that may lead to the development of guidelines in the Netherlands, by illustrating a pilot study on the viaduct Zijlweg in the Netherlands. This reinforced concrete bridge rates too low in shear. Topics of interest are the required load that the bridge has to withstand to be approved by the load test and the interpretation of the measurements during the test to avoid permanent damage to the structure. These measurements were compared to the stop criteria from existing codes for buildings, to examine if recommendations for the use with bridges can be formulated. The final result of the test on this case study is that the capacity of the viaduct is proven to be sufficient for shear and bending moment. 相似文献
16.
Mechanical Properties of an Fe‐Based SAM2×5‐630 Metallic Glass Matrix Composite with Tungsten Particle Additions 下载免费PDF全文
I‐Chung Cheng James P. Kelly Ekaterina Novitskaya Veronica Eliasson Andrea M. Hodge Olivia A. Graeve 《Advanced Engineering Materials》2018,20(9)
We present the role of tungsten additions on the mechanical properties of a Fe‐based structural amorphous metal (SAM2×5‐630) containing crystalline tungsten. Matrix cracking by microindentation is inhibited by the addition of tungsten and indicates that tungsten improves the fracture toughness. Response surfaces from nanoindentation arrays indicate that the hardness and modulus of the matrix phase are increased by tungsten additions. Bulk composites with 30 vol% tungsten subjected to 4‐point flexure exhibited brittle fracture behavior and the characteristic strength and Weibull modulus were 165 and 8.7 MPa, respectively. The addition of tungsten did not cause devitrification of the matrix phase. 相似文献
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Water Resources Management - The long-term success of water service reforms depends on sufficient revenues being collected from users to allow access to be extended and quality of service to be... 相似文献
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Determination of the Electronic Energy Levels of Colloidal Nanocrystals using Field‐Effect Transistors and Ab‐Initio Calculations 下载免费PDF全文
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Graeve Olivia A. Madadi Abhiram Kanakala Raghunath Sinha Kaustav 《Metallurgical and Materials Transactions A》2010,41(10):2691-2697
Tungsten nanopowders were synthesized by a low-temperature technique and then heat treated in a gaseous reductive atmosphere
in order to study the phase evolution, crystallite size, and particle size of the powders as the heat treatment temperature
was modified. Synthesis of the powders was carried out in aqueous media using NaBH4 as a reducing agent using careful control of the pH of the solutions. The XRD patterns of the as-synthesized powders showed
an amorphous phase. After washing, energy dispersive spectroscopy showed that the powders had peaks for oxygen and tungsten.
In order to promote crystallization and eliminate the oxygen, the powders were heat treated at 773 K, 923 K, and 1073 K (500 °C,
650 °C, and 800 °C) in a H2/CH4 reducing atmosphere for 2 hours. XRD after heat treatment showed α-W peaks for the powders treated at 1073 K and 923 K (800 °C and 650 °C) and a mixture of β-W and α-W for the powders treated at 773 K (500 °C). The crystallite sizes determined from X-ray peak broadening were 12, 16, and
20 nm, whereas the average particle sizes from dynamic light scattering were 260, 450, and 750 nm, for heat treatment temperatures
of 773 K, 923 K, and 1073 K (500 °C, 650 °C, and 800 °C), respectively. The average crystallite size and particle sizes increased
proportionally with the treatment temperature, in contrast to what has been found for some ceramics, in which as the heat
treatment temperature is increased, the crystallite size increases, but the particle size stays constant. 相似文献
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