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1.
Thyromimetics, whose physicochemical characteristics are analog to thyroid hormones (THs) and their derivatives, are promising candidates as novel therapeutics for neurodegenerative and metabolic pathologies. In particular, sobetirome (GC-1), one of the initial halogen-free thyromimetics, and newly synthesized IS25 and TG68, with optimized ADME-Tox profile, have recently attracted attention owing to their superior therapeutic benefits, selectivity, and enhanced permeability. Here, we further explored the functional capabilities of these thyromimetics to inhibit transthyretin (TTR) amyloidosis. TTR is a homotetrameric transporter protein for THs, yet it is also responsible for severe amyloid fibril formation, which is facilitated by tetramer dissociation into non-native monomers. By combining nuclear magnetic resonance (NMR) spectroscopy, computational simulation, and biochemical assays, we found that GC-1 and newly designed diphenyl-methane-based thyromimetics, namely IS25 and TG68, are TTR stabilizers and efficient suppressors of TTR aggregation. Based on these observations, we propose the novel potential of thyromimetics as a multi-functional therapeutic molecule for TTR-related pathologies, including neurodegenerative diseases.  相似文献   
2.
Metallurgical and Materials Transactions B - The quality requirements of aluminum products are steadily increasing, and the presence of non-metallic inclusions have a large impact on the quality of...  相似文献   
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4.
We discuss the performance, of a normal metal hot electron bolometer (NHEB) that we have measured at 0.3 K. We found that the noise equivalent power was limited by the amplifier noise. To improve the NHEB power response and to make it more robust and reliable we propose to substitute the normal metal with heavily doped silicon. The heavily doped silicon behaves like a metal with lower carrier concentration and has a smaller electron–phonon thermal coupling. We have fabricated superconductor-doped silicon-superconductor contacts (S-Sm-S) and we have used them as thermometers and coolers.  相似文献   
5.
Production pipelines of manufactory industries present several machines and robots in which the movements of interpolated axes are managed by computerized numerical controls (CNCs). These are typically synchronized with several other simpler actuators along the pipeline of production. CNCs have to be flexible, easily expandable, and reusable, when pipelines of production are frequently reconfigured to realize different arranged pipelines with different technical requirements. In this paper, the assessment of a flexible CNC for such reconfigurable pipelines is presented. The analysis has been focused on defining objective metrics that can be applied for assessing performance and feasibility of distributed controls for pipelines. The method proposed has been applied on the distributed control architecture defined in the MUPAAC ESPRIT HPCN (Multi Processor Architecture for Automatic Control, High Performance Computer Networking of the European Commission). MUPAAC architecture and prototype has been assessed in order to identify the critical configurations and the limits of the architecture.  相似文献   
6.
In this work a new class of numerical methods for the BGK model of kinetic equations is presented. In principle, schemes of any order of accuracy in both space and time can be constructed with this technique. The methods proposed are based on an explicit–implicit time discretization. In particular the convective terms are treated explicitly, while the source terms are implicit. In this fashion even problems with infinite stiffness can be integrated with relatively large time steps. The conservation properties of the schemes are investigated. Numerical results are shown for schemes of order 1, 2 and 5 in space, and up to third-order accurate in time.  相似文献   
7.
Preparative isoelectric focusing in multicompartment electrolyzers is based on the production of isoelectric membranes of precise isoelectric point, able to buffer at their pI value and to titrate proteins tangent to or crossing the membranes. Up to the present, such membranes have been based on polyacrylamide chemistry; acrylamide, however, is neither stable in acidic nor basic environments. We describe here novel membranes, produced with a unique monomer, N-acryloylaminoethoxyethanol (AAEE). Poly(AAEE) membranes are extremely stable to alkaline hydrolysis (500 times more stable than polyacrylamide) and even more hydrophilic than the latter matrix. This allows production of highly reproducible membranes (these do not change their pI with time, since no acrylic acid is produced by hydrolysis upon storage) which do not adsorb proteins by hydrophobic interaction.  相似文献   
8.
The redox behavior of titanium in CaO-SiO2-TiO x melts was investigated using a slag-gas equilibrium technique. Titanium partitioning between Ti3+ and Ti4+ valency states and the ratio of activity coefficients of TiO1.5 and TiO2 were determined as functions of oxygen partial pressure, temperature, and slag composition. The equilibrium experiments were carried out at temperatures between 1783 and 1903 K under CO-CO2-Ar gas atmosphere with oxygen partial pressure ranging from 10−12 to 10−7 atm (1.01×10−10 kPa to 1.01×10−5 kPa). The slags had CaO/SiO2 ratios between 0.55 and 1.35 and total titanium oxide concentrations from 7 to 50 mass pct. Experimental results showed that the Ti3+/Ti4+ ratio in CaO-SiO2-TiO x slags, containing up to 50 mass pct TiO x , increased with decreasing oxygen partial pressure and decreased with increasing CaO/SiO2 ratio and decreasing temperature. Measured variation of the redox ratio Ti3+/Ti4+ with oxygen partial pressure closely followed the ideal behavior. Increasing the CaO/SiO2 ratio increased the ratio of activity coefficients of TiO1.5 and TiO2. The effect of total titania content on this ratio was more complex and in accord with Raman spectroscopy data.  相似文献   
9.
Impedance spectroscopy and gravimetry were employed to characterize alkyd-acrylate and styrene-acrylate water-borne resin film properties during wetting-through (i.e. during water uptake).  相似文献   
10.
Interest in measuring the quality of life (QL) in relation to health care has increased enormously in recent years. This is also true for end-stage renal failure where it is important not only to provide a better survival but also the quality of that survival. The aim of this study was to assess the relative influence of different kinds of treatment on end-stage renal disease after the patients' evaluation of their overall QL. We studied 167 patients receiving conservative treatment (45), haemodialysis (44), haemodialysis and erythropoieth (36), and continuous ambulatory peritoneal dialysis (42). The patients completed an original questionnaire consisting of 37 questions divided in five groups and generating 15 QL variables: personal data (name, gender, age, basic kidney disease); sociodemographic data influenced by the illness (family history, working ability, employment status); general health characteristics (fatigue, appetite, wound healing, sleep, resistance to cold); aspects of private life that are mostly influenced by the disease (social interaction, traveling, mood, sports, sexual life), and patients subjective assessment of their condition (self care and happiness). Patients on haemodialysis showed lower levels of QL than that on peritoneal dialysis related to fatigue (p < 0.01), working ability (p < 0.05), wound healing (p < 0.05), and appetite (p < 0.01) compared to the conservative treatment. Peritoneal dialysis had also a statistically significant positive influence on fatigue (p < 0.05) compared to conservative treatment. However, erythropoletin treatment showed better results with regard to traveling (p < 0.05), resistance to cold (p < 0.01), self care (p < 0.05) and mood (p < 0.05) compared to peritoneal dialysis, and working ability (p < 0.05), fatigue (p < 0.05) and mood (p < 0.05) compared to conservative treatment and haemodialysis.  相似文献   
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