Infection with hepatitis C virus (HCV) is a major public health problem. In fact, chronic HCV is a leading cause of cirrhosis, hepatocellular carcinoma, and death from liver disease in most ...countries. The advent of highly effective oral direct-acting antiviral therapy is the most significant advance in the treatment of HCV in decades and now allows us to cure chronic HCV. However, a large number of infected patients have not been diagnosed since hepatitis C is a largely asymptomatic disease. Thus, it is fundamental to improve the screening system in order to identify individuals who are currently infected and to treat them. Risk-based hepatitis C testing and birth cohort screening have had limited success and many patients living with the infection are not aware of their status. Universal screening for HCV is a tremendous improvement compared with the previous strategies. Indeed, global screening leads to the appropriate identification and treatment of all individuals chronically infected with HCV and prevents the progression of liver disease and the associated morbidity and mortality. In addition, universal HCV testing appears to be cost-effective. In this article, we review the current barriers to HCV eradication and the different strategies for HCV infection screening.
We report on the elastic properties of xMnO‐Al2O3‐(6‐x)SiO2 manganese aluminosilicate glasses, in which pronounced exchange coupling and antiferromagnetic interaction occurs among the paramagnetic ...Mn2+ ions. X‐ray absorption reveals a Mn‐O bond length of ∼2.1 Å, and a distance of ∼3 Å between Mn2+ ions in sixfold coordination, further corroborated by electron paramagnetic resonance and dynamic photoluminescence spectroscopy. This indicates the presence of edge‐sharing MnO6 units, in resemblance to edge‐sharing MnO8 in the crystalline Spessartine garnet Mn3Al2SiO43. We argue that these cluster species have a profound effect on material stiffness: the compact structure of manganese aluminosilicate glasses enables a Young's modulus in the 100 GPa range and a Poisson's ratio of about 0.3. This exceeds the compositional trend with cation field strength observed for other aluminosilicate glasses.
We report on the lateral hardness of glasses from the Na2O-CaO-SiO2 (NCS) system, including CS and NS binaries. Quantitative data are provided on the work of lateral deformation, obtained through ...instrumented indentation by monitoring the lateral force as a function of normal load. Experiments were conducted in the regime of elastic-plastic deformation, that is, in the absence of microscopic cracking for normal loads of 50–70 mN. The scratch hardness is determined from the work of deformation per deformed volume. Parallel observations of the elastic properties are undertaken so as to reference scratching data to glass composition and structure. We find that structural densification and high rigidity favor higher scratch hardness. For the considered range of chemical compositions, the scratch hardness exhibits an approximately linear correlation with bulk modulus and packing density. It increases in the direction of compositions with higher content of CaO, and decreases with the content of Na2O. Furthermore, we find a strongly linear correlation between scratch hardness and the deviation of experimental compressibility from the mean-field estimate of the Makishima-Mackenzie model. This points to the importance of intermediate-range structural heterogeneity in the scratching process.
•Lateral nano-indentation is employed for quantifying scratching-behaviour of NCS glasses.•Work of deformation and scratch hardness are deduced from lateral force analysis.•Relations between NBO concentration, intermediate-range heterogeneity and scratch resistance are discussed.
In this work, we prepared electrically conductive self-healing nanocomposites. The material consists of multi-walled carbon nanotubes (MWCNT) that are dispersed into thermally reversible crosslinked ...polyketones. The reversible nature is based on both covalent (Diels-Alder) and non-covalent (hydrogen bonding) interactions. The design allowed for us to tune the thermomechanical properties of the system by changing the fractions of filler, and diene-dienophile and hydroxyl groups. The nanocomposites show up to 1 × 10
S/m electrical conductivity, reaching temperatures between 120 and 150 °C under 20-50 V. The self-healing effect, induced by electricity was qualitatively demonstrated as microcracks were repaired. As pointed out by electron microscopy, samples that were already healed by electricity showed a better dispersion of MWCNT within the polymer. These features point toward prolonging the service life of polymer nanocomposites, improving the product performance, making it effectively stronger and more reliable.
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