Publications by authors named "F P R de Villiers"
Drought has a significant, negative impact on crop production; and these effects are poised to increase with climate change. Plants acclimate to drought and water stress through diverse physiological responses, primarily mediated by the hormone abscisic acid (ABA). Because plants lose the majority of their water through stomatal pores on aerial surfaces of plants, stomatal closure is one of the rapid responses mediated by ABA to reduce transpirational water loss.
View Article and Find Full Text PDFBackground: While fluoroscopic guidance is currently the imaging standard for cervical medial branch blocks (CMBBs), ultrasound guidance (USG) offers several potential safety advantages such as real-time needle visualization and the ability to detect and avoid critical soft tissue vascular or neural structures. However, no large-scale trials have examined the safety of USG for CMBB.
Methods: Five hundred patients undergoing 2308 individual block levels were recruited using a prospective cohort design, and blocks were performed in an outpatient office setting using an in-plane USG technique.
Article Synopsis
- This study explores the aging rates and longevity of ectothermic tetrapods, specifically nonavian reptiles and amphibians, using data from 107 wild populations across 77 species.
- It investigates how factors like thermoregulatory methods, environmental temperature, and life history strategies influence demographic aging among these animals.
- The findings reveal that ectotherms exhibit more diverse aging rates than endotherms and show instances of negligible aging, highlighting the importance of studying these species to better understand the evolution of aging.
Uranium is a naturally occurring radionuclide that is absorbed by plants and interferes with many aspects of their physiology and development. In this study, we used an ionomic, metalloproteomic, and biochemical approach to gain insights into the impact of uranyl ions on the proteome of Arabidopsis thaliana cells. First, we showed that most of the U was trapped in the cell wall and only a small amount of the radionuclide was found in the cell-soluble fraction.
View Article and Find Full Text PDFBackground: Although the value of ultrasound-guided (USG) lumbar medial branch blocks (MBB) has previously been examined in several clinical trials, blocking the L5 dorsal ramus (DR) remains a technical challenge and we sought to examine the accuracy of a novel technique targeting this level.
Methods: In this prospective cohort study, 115 patients scheduled for an L4 MBB and L5 DR block underwent an ultrasound scan to assess their lower spine sonoanatomy. Subjects in whom the necessary landmarks could be visualized underwent a USG L5 DR block using a pivot technique, which involved redirecting a needle from its position on the L5 transverse process after an L4 MBB.