“Remember—healthy pee is 1 to 3, 4 to 8 you must hydrate!” So goes a rhyming couplet from the Think Kidneys website, the online presence of the Transforming Participation in Chronic Kidney Disease programme. It comes with a colour chart, not unlike those available in shops selling paint, ranging from the off-white shade 1 (good) to shade 8, which I’d describe as orange with a hint of rust (seve...

Abiotic stress is one of the primary constraints limiting the range and success of arthropods, and nowhere is this more apparent than Antarctica. Antarctic arthropods have evolved a suite of adaptations to cope with extremes in temperature and water availability. Here, we review the current state of knowledge regarding the environmental physiology of terrestrial arthropods in Antarctica. To sur...

Leaf shrinkage with dehydration has attracted attention for over 100 years, especially as it becomes visibly extreme during drought. However, little has been known of its correlation with physiology. Computer simulations of the leaf hydraulic system showed that a reduction of hydraulic conductance of the mesophyll pathways outside the xylem would cause a strong decline of leaf hydraulic conduct...

Abstract Species introduced by human activities can alter the normal functioning of ecosystems promoting negative impacts on native biodiversity, as they rapidly expand their population size, demonstrating phenotypic plasticity and possible adaptive capacity to novel environments. Twenty years ago, guttural toad, Sclerophrys gutturalis, was a peri-urban area Cape Town, with cooler drier climati...

Yeasts grow at very different potassium concentrations, adapting their intracellular cation levels to changes in the external environment. Potassium homeostasis is maintained with the help of several transporters mediating the uptake and efflux of potassium with various affinities and mechanisms. In the model yeast Saccharomyces cerevisiae, two uptake systems, Trk1 and Trk2, are responsible for...

Xylem cavitation resistance has profound implications for plant physiology and ecology. This process is characterized by a 'vulnerability curve' (VC) showing the variation of the percentage of cavitation as a function of xylem pressure potential. The shape of this VC varies from 'sigmoidal' to 'exponential'. This review provides a panorama of the techniques that have been used to generate such ...

Characterizing the collagen fiber orientation and organization in the eye is necessary for a complete understanding of ocular biomechanics. In this study, we assess the performance of polarized light microscopy to determine collagen fiber orientation of ocular tissues. Our results demonstrate that the method provides objective, accurate, repeatable and robust data on fiber orientation with µm-s...

While I was on my recent pediatrics rotation at medical school, I must have seen about 20 children present to the emergency department with the manifestations of dehydration owing to acute diarrhea. In line with World Health Organization guidelines, these children’s dehydration status was categorized into three grades: none, mild, and severe, corresponding to dehydration 3%, between 3% and 8%, ...

nowadays, hydrogels are widely used as wound dressings in biomedical applications. similar to other types of the moist (wet) wound dressings, it is necessary to have sufficient information about their dehydration kinetics during the pre-usage period (e.g. storage duration) and also the wound healing process. in this work, hydrogel wound dressings based on polyvinyl alcohol were prepared by cycl...