Obtaining traces at high ATP concentration was challenging due to the small available field of view and rapid detachment of myosin from actin caused by the faster stepping rate.
In this setting, interpretation of the alterations in individual nutrient concentrations is challenging as several physical, chemical, environmental and other unknown factors may be at play.
As has been illustrated in adults, even in the context of a clinical trial, achieving target drug concentrations is challenging, especially early after transplant [ 40].
Accurate quantifications of absolute in vivo concentrations are challenging due to different chemical properties of different peptides which result in diverging affinities for extraction and/or purification.
Predicting the individual dose requirement to achieve and maintain the desired target whole blood concentration of tacrolimus is challenging due to considerable variability in apparent whole blood clearance (CL/F) between patients [coefficient of variance (CV) 30 42 %] as well as between dosing occasions within patients (CV 40 71 %) [ 3].
(9) Assessing the risk of adverse effects of such fluctuating concentrations to aquatic organisms is challenging, because traditional risk assessment methods are based on ecotoxicological tests, employing constant exposure concentrations and fixed durations, that do not explicitly consider the temporal aspect of toxicity.
Expanding the diverse detectable metabolome over a broad range of concentration, physical and chemical properties is challenging yet crucial since multiple pathways can often be influenced by a single external variable.
It is important to recognize that the amount of dye applied to cells, tissues, or organisms may differ substantially from the intracellular concentration, and the only way to truly define how much dye is present is to measure the concentration inside cells, although this is challenging unless the probe is ratiometric.
However, controlling the carrier type and concentration of dopants in graphene films is challenging, especially for fabrication of p-type films.
