Scorpions have been shown to control their venom usage in defensive encounters, depending on the perceived threat. Potentially, the venom amount that is injected could be controlled by reducing the flow speed, the flow duration, or both. We here investigated these variables by allowing scorpions to sting into an oil-filled chamber, and recording the accreting venom droplets with high-speed video. The size of the spherical droplets on the video can then be used to calculate their volume. We recorded defensive stings of 20 specimens representing 5 species. Significant differences in the flow rate and total expelled volume were found between species. These differences are likely due to differences in overall size between the species. Large variation in both venom flow speed and duration are described between stinging events of single individuals. Both venom flow rate and flow duration correlate highly with the total expelled volume, indicating that scorpions may control both variables in order to achieve a desired end volume of venom during a sting.
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http://dx.doi.org/10.1016/j.toxicon.2015.04.011 | DOI Listing |
Biomed Phys Eng Express
January 2025
Brain Health Imaging Centre, Centre for Addiction and Mental Health, B68-250 College St, Toronto, Ontario, M5T 1R8, CANADA.
Objective: Arterial sampling for PET imaging often involves continuously measuring the radiotracer activity concentration in blood using an automatic blood sampling system (ABSS). We proposed and validated an external delay and dispersion correction procedure needed when a change in flow rate occurs during data acquisition. We also measured the external dispersion constant of [11C]CURB, [18F]FDG, [18F]FEPPA, and [18F]SynVesT-1.
View Article and Find Full Text PDFPLoS One
January 2025
North China University of Water Resources and Electric Power, Zhengzhou City, Henan Province, P.R. China.
This study employs electrical resistivity tomography (ERT) to experimentally investigate the migration characteristics of light non-aqueous phase liquids (LNAPL) under various groundwater conditions. Through cross-hole measurements and time-lapse inversion, the migration process of LNAPL under three scenarios-unsaturated conditions, constant groundwater levels, and declining water levels-was systematically analyzed. The results indicate that LNAPL migration behavior exhibits significant differences under different conditions.
View Article and Find Full Text PDFPLoS One
January 2025
Transplant Group, La Paz University Hospital Health Research Institute (IdiPAZ), Madrid, Spain.
Background: Intestinal transplantation (ITx) represents the only curative option for patients with irreversible intestinal failure. Nevertheless, its rejection rate surpasses that of other solid organ transplants due to the heightened immunological load of the gut. Regulatory T-cells (Tregs) are key players in the induction and maintenance of peripheral tolerance, suggesting their potential involvement in modulating host vs.
View Article and Find Full Text PDFInt J Gynaecol Obstet
January 2025
Effective Care Research Unit, University of the Witwatersrand and Walter Sisulu University, East London, South Africa.
Objective: To compare low-cost "Suction Tube Uterine Tamponade" (STUT) treatment for refractory postpartum hemorrhage (PPH) with uterine balloon tamponade (UBT) using a randomized feasibility study.
Methods: After verbal assent, we allocated participants with refractory PPH by randomly ordered envelopes to STUT or routine UBT at 10 hospitals in South Africa and one tertiary referral center in Colombia between January 10, 2020, and May 3, 2024. In the STUT group, we inserted a 24 FG Levin stomach tube into the uterine cavity and applied suction.
Bioresour Bioprocess
January 2025
Biotechnology Processes Unit, IMDEA Energy, Avda. Ramón de la Sagra 3, Móstoles, Madrid, 28935, Spain.
This research investigated the acidogenic fermentation (AF) of sugar cane molasses in an up-flow anaerobic sludge blanket (UASB) reactor for the production of carboxylates. The first step was to assess the optimum process temperature (25, 35 or 55 ºC) using two different granular inocula, one from a brewery company (BGS) and other from a paper plant company (PGS). These experiments determined that the most suitable temperature for carboxylates production was 25 ºC, obtaining higher bioconversions (27.
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