Interplay between epigallocatechin-3-gallate and ionic strength during amyloid aggregation

The formation and accumulation of protein amyloid aggregates is linked with multiple amyloidoses, including neurodegenerative Alzheimer’s or Parkinson’s disease. The mechanism of such fibril formation is impacted by various environmental conditions, which greatly complicates the search for potential anti-amyloid compounds. One of these factors is solution ionic strength, which varies between different aggregation protocols during in vitro drug screenings. In this work, we examine the interplay between ionic strength and a well-known protein aggregation inhibitor—epigallocatechin-3-gallate. We show that changes in solution ionic strength have a major impact on the compound’s inhibitory effect, reflected in both aggregation times and final fibril structure. We also observe that this effect is unique to different amyloid-forming proteins, such as insulin, alpha-synuclein and amyloid-beta.

Short- and Long-Term Effects of Lime and Gypsum Applications on Acid Soils in a Water-Limited Environment: 3. Soil Solution Chemistry

Aluminum (Al) toxicity imposes a significant limitation to crop production in South Western Australia. This paper examines the impact of surface-applied lime and gypsum on soil solution chemistry in the short term (1 year) and the long-term (10 years) in water limited environments. In the experiments, we measured soil solution chemistry using a paste extract on soil profile samples collected to a depth of 50 cm. We then used the chemical equilibrium model MINTEQ to predict the presence and relative concentrations of Al species that are toxic to root growth (Al associated with Al3+ and AlOH2 or Toxic-Al) and less non-toxic forms of Al bound with sulfate, other hydroxide species and organic matter. A feature of the soils used in the experiment is that they have a low capacity to adsorb sulfate. In the short term, despite the low amount of rainfall (279 mm), sulfate derived from the surface gypsum application is rapidly leached into the soil profile. There was no self-liming effect, as evidenced by there being no change in soil solution pH. The application of gypsum, in the short term, increased soil solution ionic strength by 524–681% in the 0–10 cm soil layer declining to 75–109% in the 30–40 cm soil layer due to an increase in soil solution sulfate and calcium concentrations. Calcium from the gypsum application displaces Al from the exchange sites to increase soil solution Al activity in the gypsum treatments by 155–233% in the short term and by 70–196% in the long term to a depth of 40 cm. However, there was no effect on Toxic-Al due to Al sulfate precipitation. In the long term, sulfate leaching from the soil profile results in a decline in soil solution ionic strength. Application of lime results in leaching of alkalinity into the soil profile leading to a decreased Toxic-Al to a depth of 30 cm in the long term, but it did not affect Toxic-Al in the short term. Combining an application of lime with gypsum had the same impact on soil solution properties as gypsum alone in the short term and as lime alone in the long term.

Ionic strength and polyelectrolyte molecular weight effects on floc formation and growth in Taylor–Couette flows

A Taylor–Couette cell capable of radial injection was used to study the effects of varying solution ionic strength and polyelectrolyte molecular weight on the polyelectrolyte-driven flocculation of bentonite suspensions.

Influence of pH and Concentration of Ionic Strength Adjuster (ISA) on the Performance of Nd(III) Ion Selective Electrodewith 4-Sebacoylbis(1-Phenyl-3-Methyl-5-Pyrazolone)(H2SbBP) as Ionophores

4-Sebacoylbis (1-phenyl-3-methyl-5-pyrazolone) (H2SbBP) ligand has been successfully synthesized, characterized and used as ionophores in Nd (III) selective electrode, using polytetrafluoroethylene (PTFE) membranous as a support. Prior to use the PTFE membrane soaked ionophores 1.5% w/v in chloroform for 24 hours. The performance of electrode studied by seeing the influence of pH and concentration of KNO3 as a buffer solution ionic strength. Variations in pH of the solution was set at pH ranges between 1 to 10 using a solution of HCl and NaOH, while KNO3 concentration varied between 10-4 to 10-1 M. Nd3+ concentration range is between 10-6 up to 10-2 M. The best electrode performance was obtained at pH 5 and 10-2 M KNO3 concentration with a sensitivity of (18.5 ± 0.2) mV/decade and its response time less than 25 seconds.

A confinement strategy to prepare N-doped reduced graphene oxide foams with desired monolithic structures for supercapacitors

N-Doped reduced graphene foam was obtained by one-step hydrothermal reaction by the confinement of solution ionic strength.