Lipid Transfer to HDL is Higher in Marathon Runners than in Sedentary Subjects,but is Acutely Inhibited During the Run

Although exercise increases HDL-cholesterol, exercise-induced changes in HDL metabolism have been little explored. Lipid transfer to HDL is essential for HDL’s role in reverse cholesterol transport. We investigated the effects of acute exhaustive exercise on lipid transfer to HDL. We compared plasma lipid, apolipoprotein and cytokine levels and in vitro transfer of four lipids from a radioactively labeled lipid donor nanoemulsion to HDL in sedentary individuals (n = 28) and in marathon runners (n = 14) at baseline, immediately after and 72 h after a marathon. While HDL-cholesterol concentrations and apo A1 levels were higher in marathon runners, LDL-cholesterol, apo B and triacylglycerol levels were similar in both groups. Transfers of non-esterified cholesterol [6.8 (5.7–7.2) vs. 5.2 (4.5–6), p = 0.001], phospholipids [21.7 (20.4–22.2) vs. 8.2 (7.7–8.9), p = 0.0001] and triacylglycerol [3.7 (3.1–4) vs. 1.3 (0.8–1.7), p = 0.0001] were higher in marathon runners, but esterified-cholesterol transfer was similar. Immediately after the marathon, LDL- and HDL-cholesterol concentrations and apo A1 levels were unchanged, but apo B and triacylglycerol levels increased. Lipid transfer of non-esterified cholesterol [6.8 (5.7–7.2) vs. 5.8 (4.9–6.6), p = 0.0001], phospholipids [21.7 (20.4–22.2) vs. 19.1 (18.6–19.3), p = 0.0001], esterified-cholesterol [3.2 (2.2–3.8) vs. 2.3 (2–2.9), p = 0.02] and triacylglycerol [3.7 (3.1–4) vs. 2.6 (2.1–2.8), p = 0.0001] to HDL were all reduced immediately after the marathon but returned to baseline 72 h later. Running a marathon increased IL-6 and TNF-α levels, but after 72 h these values returned to baseline. Lipid transfer, except esterified-cholesterol transfer, was higher in marathon runners than in sedentary individuals, but the marathon itself acutely inhibited lipid transfer. In light of these novel observations, further study is required to clarify how these metabolic changes can influence HDL composition and anti-atherogenic function.     

Quantifying dissipative contributions in nanoscale interactions

Imaging with nanoscale resolution has become routine practice with the use of scanning probe techniques. Nevertheless, quantification of material properties and processes has been hampered by the complexity of the tip-surface interaction and the dependency of the dynamics on operational parameters. Here, we propose a framework for the quantification of the coefficients of viscoelasticity, surface energy, surface energy hysteresis and elastic modulus. Quantification of these parameters at the nanoscale will provide a firm ground to the understanding and modelling of tribology and nanoscale sciences with true nanoscale resolution.     

Gold-Nanoparticle-Decorated Metal-Organic Frameworks for Anticancer Therapy

Confinement of Au nanoparticles (NPs) within the porous materials with few nanometers (2-3 nm) has been a well established research area in the past decades in heterogeneous catalysis mainly due to the unique behaviour of Au NPs than its bulk counterpart. In this aspect, Au NPs encapsulated within the pore volumes of metal−organic frameworks (MOFs) have been intensively explored as heterogeneous solid catalysts for wide range of reactions. In recent years, Au NPs confined within the porous MOFs along with the photosensitizer or drug have been effectively used for the treatment of tumor cells through the generation of reactive oxygen species via cascade reactions. This work highlights the benefits of MOFs pores in the preparation of nanomedicine with high efficiency by assembling Au NPs, photosensitizer/drug with the combination of laser either for imaging or treatment of tumor cells. Further, the existing literature is grouped based on the nature of porous materials employed in the preparation of nanomedicine. The final section comments on our view on future developments in the field.     

Synthesis and ex-situ evaluation of quaternized polysulfone as an anion exchange ionomer for AEM technologies

Anion exchange ionomer (AEI) is a critical component used on anion exchange membrane fuel cell (AEMFC) and alkaline water electrolyzer (AWE). In this work, quaternized polysulfone with different functionalization degree were used as an ionomer to evaluate the performance in the oxygen reduction reaction (ORR) and hydrogen oxidation reaction (HOR), both implied in the operation of AEMFC and AWE. The synthesized ionomer exhibited a better performance in both reactions in comparison to the commercial AEI Aemion®. PSf-130 exhibited better performance, since IEC and surface area increases twice regarding the same parameters in the PSf-60. The PSf-130 conductivity increases three times regarding the value exhibited by PSf-60. Finally, the J_lim and J_k increases 67% and 100% for ORR. On the other hand, the same catalytic parameter increased 44% and 35% for HOR comparing both polysulfone-based ionomers. The Tafel slope values do not showed drastically changes for different ionomers indicating the same rate determining step (RDS) and the same mechanism in both reactions for all the ionomers.     

GAS-LIQUID REACTORS WITH VOLATILE LIQUID REACTANTS: APPROXIMATE SOLUTION FOR CONSECUTIVE BIMOLECULAR REACTIONS OF GENERAL ORDER

An approximate solution of the film model in presence of volatile liquid reactants is presented for the case of a general van de Vusse-like reaction scheme and general power-law reaction rates. The solution is obtained in a closed-form and simply requires the numerical solution of a system of nonlinear equations. The developed approximate solution is valid for any reaction regime and any number of reactions taking place within the liquid him. The application to a CSTR is discussed; this also serves as a test of the accuracy of the approximate solution carried out by comparison with the complete film model solved via the orthogonal collocation method. The numerical studies show that the approximate solution can be used with confidence for the usual encountered rate laws and that the volatility of the liquid reactants affects the performance of the CSTR mostly at the intermediate value of the Halt a number.     

Catalytic Reduction of 4-Nitrobenzoic Acid by cis-[Rh(CO)2(Amine)2](PF6) Complexes Under Water–Gas Shift Reaction Conditions: Kinetics Study

Rhodium(I) complexes of the type, cis-[Rh(CO)₂(amine)₂](PF₆) where (amine = 3-picoline, 2-picoline, pyridine, 2,6-lutidina or 3,5-lutidine) dissolved in 80% aqueous amine solutions catalyzed the selective reduction of 4-nitrobenzoic acid to 4-aminobenzoic acid under CO atmosphere. The importance of these catalytic systems is their high chemo selectivity for the aromatic nitro group of the 4-nitrobenzoic acid with respect to the carboxylic group, allowing the production of the desired aromatic amine in high yields. The 4-aminobenzoic acid production depends on the nature of the coordinated amine. The Rh/3,5-lutidine system, the most active catalyst among tested, displays turnover frequencies for 4-aminobenzoic acid production of about 173 moles per mole Rh per day for [Rh] = 1 × 10^?4 mol, [4-nitrobenzoic acid] = 3.82 × 10^?3mol, 10 mL of 80% aqueous 3,5-lutidine, P(CO) = 0.9 atm at 100 °C. Analyses of kinetic results for the Rh/3,5-lutidine system show a first order dependence on 4-nitrobenzoic acid concentration, a non-linear dependence on CO pressure, a segmented Arrhenius plot and dependence on the nature of the reducing gas agent. These data are discussed in terms of a possible mechanism.     

Mechanical and dynamical mechanical properties of chloroprene rubber and cellulose II composites

Vulcanized composites of chloroprene rubber (CR) with cellulose II (Cel II) as a filler were investigated. Cel II, obtained by the coagulation of cellulose xanthate, was incorporated in the rubber by the traditional method. The filler content varied from 0 to 30 phr. For comparison purposes, carbon black (CB)–CR composites were also studied. The CB amount varied from 0 to 45 phr. The mechanical and dynamic mechanical properties were determined, and the CR composite containing 20 phr of Cel II showed the best set of properties. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2425–2430, 2004     

Characterisation of surface oxidation of nickel-titanium alloy by ion-beam and electrochemical techniques

The passivating effects produced on Ni₄₉Ti₅₁ (at.%) shape memory alloy by electropolishing in methanol-sulphuric acid electrolyte or thermal treatment in air are investigated with ion-beam techniques (secondary ion mass spectrometry (SIMS) and mass resolved ion scattering spectrometry (MARISS)) and electrochemical techniques (polarisation curves, photocurrent spectroscopy and impedance). Electropolishing produces a limited passivation due to formation of a thin layer of amorphous TiO₂, which causes only a slight hindrance to the oxygen evolution reaction. Thermal treatment in air at 450 °C causes a more substantial passivation due to formation of a thick oxide layer, estimated at about 80 nm for a 16 h treatment on the basis of weight increase, disregarding roughness. Data indicate that the film produced by thermal oxidation has probably a duplex structure, with a porous outer layer with inclusions of Ni species and a compact inner layer, in contact with the substrate, consisting of (essentially) nickel free TiO₂ rutile.