This work studies water permeability properties of human aquaporin 1 (hAQP1) expressed in Xenopus laevis oocyte membranes, applying a technique where cellular content is replaced with a known medium, with the possibility of measuring intracellular pressure. Consequences on water transport-produced by well-known anisotonic gradients and by the intracellular effect of probable aquaporin inhibitors-were tested. In this way, the specific intracellular inhibition of hAQP1 by the diuretic drug furosemide was demonstrated. In addition, experiments imposing anisotonic mannitol gradients with a constant ionic strength showed that the relationship between water flux and the applied mannitol gradient deflects from a perfect osmometer response when the gradient is higher than 150 mosmol kg (W) (-1) . These results would indicate that the passage of water molecules through hAQP1 may have a maximum rate. As a whole, this work demonstrates the technical advantage of controlling both intracellular pressure and medium composition in order to study biophysical properties of hAQP1, and contributes information on water channel behavior under osmotic challenges and the discovery of new inhibitors.

When new members join a working group dedicated to scientific research, several changes occur in the group's dynamics. From a teaching point of view, a subsequent challenge is to develop innovative strategies to train new staff members in creative thinking, which is the most complex and abstract skill in the cognitive domain according to Bloom's revised taxonomy. In this sense, current technological and digital advances offer new possibilities in the field of education. Computer simulation and biological experiments can be used together as a combined tool for teaching and learning sometimes complex physiological and biophysical concepts. Moreover, creativity can be thought of as a social process that relies on interactions among staff members. In this regard, the acquisition of cognitive abilities coexists with the attainment of other skills from psychomotor and affective domains. Such dynamism in teaching and learning stimulates teamwork and encourages the integration of members of the working group. A practical example, based on the teaching of biophysical subjects such as osmosis, solute transport, and membrane permeability, which are crucial in understanding the physiological concept of homeostasis, is presented.

Aortic cross‐clamping is a common strategy during vascular surgery, however, its instantaneous impact on hemodynamics is unknown. We, therefore, developed two numerical models to estimate the immediate impact of aortic clamping on the vascular properties. To assess the validity of the models, we recorded continuous invasive pressure signals during abdominal aneurysm repair surgery, immediately before and after clamping. The first model is a zero‐dimensional (0D) three‐element Windkessel model, which we coupled to a gradient‐based parameter estimation algorithm to identify patient‐specific parameters such as vascular resistance and compliance. We found a 10% increase in the total resistance and a 20% decrease in the total compliance after clamping. The second model is a nine‐artery network corresponding to an average human body in which we solved the one‐dimensional (1D) blood flow equations. With a similar parameter estimation method and using the results from the 0D model, we identified the resistance boundary conditions of the 1D network. Determining the patient‐specific total resistance and the distribution of peripheral resistances through the parameter estimation process was sufficient for the 1D model to accurately reproduce the impact of clamping on the pressure waveform. Both models gave an accurate description of the pressure wave and had a high correlation (R2 > .95) with experimental blood pressure data.

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