Although headache incidence was not high, results suggest an increased susceptibility to physiological effects of CO(2) in-flight.

No abstract

CO2 exposure training is an important tool to educate astronauts about their potential acute CO2 symptoms. Wide interindividual and temporal variations were observed in symptoms reported during astronaut CO2 exposure training. Headache could not be relied on as a marker of acute exposure during testing since fewer than half the subjects reported it. Our results support periodic refresher training since symptoms may change over time. Further study is needed to determine the optimal interval of training to maximize symptom recognition and inform operational decisions.Law J, Young M, Alexander D, Mason SS, Wear ML, Méndez CM, Stanley D, Meyers Ryder V, Van Baalen M. Carbon dioxide physiological training at NASA. Aerosp Med Hum Perform. 2017; 88(10):897-902.

The Ti–6Al–4V alloy is used for biomedical implants due to its corrosion resistance and biocompatibility, associated with the spontaneous formation of TiO2 oxide. However, the native film may be flawed and after some time of implantation in the body it may release metal ions. Oxides of higher thickness than naturally grown can be produced by anodic oxidation. The objective of this study was to evaluate the corrosion resistance of anodic TiO2 coatings, evaluating the influence of the thickness and crystalline structure of the coatings. Amorphous coatings were obtained from 27 to 140 nm that crystallized in anatase and rutile phases by heat treatment. The corrosion resistance was evaluated by potentiodynamic measurements in 0.9% sodium chloride, which is the main component of physiological solution. Evaluation of the electrochemical parameters showed that anodic coatings are more efficient barrier than the natural TiO2 oxide. As the oxidation processes influenced the electrochemical properties of metals by altering the resistance to corrosion, therefore they become important to study the electrochemical behavior of the oxides by electrochemical impedance spectroscopy.

In the present work, the inhibitory effect of Ilex paraguariensis (Yerba Mate) extract on the corrosion of aluminum in 0.1 M HCl solution, in the temperature range of 298–323 K, was studied by using weight loss tests, potentiodynamic polarization measurements and electrochemical impedance spectroscopy (EIS). The extract of Ilex paraguariensis exhibits improved inhibitory action as its concentration increases while its performance is maintained despite an increase in temperature. EIS theoretical data according to a suitable proposed equivalent circuit were successfully fitted to the experimental data. The adsorption of organic compounds followed a modified Langmuir isotherm behaviour. Derived thermodynamic parameters indicate the occurrence of both chemical and physical adsorption.

No abstract

No abstract

No abstract