890 research outputs found
Evaluation of Ice-Melting Capacities of Deicing Chemicals
Common deicing chemicals include sodium chloride, magnesium chloride, calcium chloride, calcium magnesium acetate, potassium acetate, potassium formate, and corn or beet-based deicer solution. Liquid deicers are commonly used for pre-wetting road salt, sand or other solid deicers, or mixed with salt brine as liquid deicer. Although manufacturers provide performance data under specific conditions, a standardized test is very much needed. Samples of sodium chloride, magnesium chloride, calcium chloride, potassium acetate, and beet juice-based chemical deicers were selected for performance evaluation. The SHRP Ice-Melting Capacity Test has been used in many research projects, but the results do not always correlate well with field data. A simple and economical test has been developed to evaluate the ice-melting capacities of deicing chemicals using a martini shaker, which shows some potential to become a standardized test for ice-melting capacity evaluation. Field data was collected by the Nebraska Dept. of Roads using automatic vehicle location (AVL) and the maintenance decision support system (MDSS) installed on some plow trucks. The AVL takes roadway pictures from the cab and records vehicle location. The MDSS collects weather data from area weather stations. Although initial shaker test results correlate well with known deicer performance and limited field data provided by MDSS, further development work is necessary before the shaker test can be considered for official use
Evaluation of Ice-Melting Capacities of Deicing Chemicals
Common deicing chemicals include sodium chloride, magnesium chloride, calcium chloride, calcium magnesium acetate, potassium acetate, potassium formate, and corn or beet-based deicer solution. Liquid deicers are commonly used for pre-wetting road salt, sand or other solid deicers, or mixed with salt brine as liquid deicer. Although manufacturers provide performance data under specific conditions, a standardized test is very much needed. Samples of sodium chloride, magnesium chloride, calcium chloride, potassium acetate, and beet juice-based chemical deicers were selected for performance evaluation. The SHRP Ice-Melting Capacity Test has been used in many research projects, but the results do not always correlate well with field data. A simple and economical test has been developed to evaluate the ice-melting capacities of deicing chemicals using a martini shaker, which shows some potential to become a standardized test for ice-melting capacity evaluation. Field data was collected by the Nebraska Dept. of Roads using automatic vehicle location (AVL) and the maintenance decision support system (MDSS) installed on some plow trucks. The AVL takes roadway pictures from the cab and records vehicle location. The MDSS collects weather data from area weather stations. Although initial shaker test results correlate well with known deicer performance and limited field data provided by MDSS, further development work is necessary before the shaker test can be considered for official use
A novel formulation of glucose‐sparing peritoneal dialysis solutions with l‐carnitine improves biocompatibility on human mesothelial cells
The main reason why peritoneal dialysis (PD) still has limited use in the management of patients with end‐stage renal disease (ESRD) lies in the fact that the currently used glucose‐based PD solutions are not completely biocompatible and determine, over time, the degeneration of the peritoneal membrane (PM) and consequent loss of ultrafiltration (UF). Here we evaluated the biocompatibility of a novel formulation of dialytic solutions, in which a substantial amount of glucose is replaced by two osmometabolic agents, xylitol and L‐carnitine. The effect of this novel formulation on cell viability, the integrity of the mesothelial barrier and secretion of pro‐inflammatory cytokines was evaluated on human mesothelial cells grown on cell culture inserts and exposed to the PD solution only at the apical side, mimicking the condition of a PD dwell. The results were compared to those obtained after exposure to a panel of dialytic solutions commonly used in clinical practice. We report here compelling evidence that this novel formulation shows better performance in terms of higher cell viability, better preservation of the integrity of the mesothelial layer and reduced release of pro‐inflammatory cytokines. This new formulation could represent a step forward towards obtaining PD solutions with high biocompatibility
Conspiracy beliefs, regulatory self-efficacy and compliance with COVID-19 health-related behaviors: The mediating role of moral disengagement
Although recent studies on the 2019 coronavirus disease (COVID-19) have highlighted the negative effects of moral disengagement on intentions to comply with COVID-19 containment measures, little is known about the mediating role of moral disengagement in the relationship between regulatory self-efficacy in complying with the containment measures, beliefs in conspiracy theories and compliance with COVID-19 health-related behaviors. Data were collected from 1164 young adults (women, N = 796; 68.4%; mean age 25.60 ± 4.40 years) who completed an online survey from 15th May to 22nd June 2021. Results of the multi-group path analyses indicated that higher beliefs in conspiracy theories were associated with lower compliance with COVID-19 health-related behaviors, whereas higher self-efficacy beliefs in complying with the containment measures were associated with higher compliance with COVID-19 health-related behaviors. Moral disengagement significantly mediated the associations between beliefs in conspiracy theories, regulatory self-efficacy, and compliance with COVID-19 health-related behaviors. Finally, the tested model was gender-invariant. Findings suggest that public health authorities and social care professionals should promote interventions aimed at improving regulatory self-efficacy, emphasizing the moral significance of respecting or ignoring the recommended COVID-19 measures (e.g., physical distance in public), and enhancing people's concern for the potential harms of their immoral actions
Termination of cAMP signals by Ca2+ and Gαi via extracellular Ca2+ sensors: a link to intracellular Ca2+ oscillations
Termination of cyclic adenosine monophosphate (cAMP) signaling via the extracellular Ca2+-sensing receptor (CaR) was visualized in single CaR-expressing human embryonic kidney (HEK) 293 cells using ratiometric fluorescence resonance energy transfer–dependent cAMP sensors based on protein kinase A and Epac. Stimulation of CaR rapidly reversed or prevented agonist-stimulated elevation of cAMP through a dual mechanism involving pertussis toxin–sensitive Gαi and the CaR-stimulated increase in intracellular [Ca2+]. In parallel measurements with fura-2, CaR activation elicited robust Ca2+ oscillations that increased in frequency in the presence of cAMP, eventually fusing into a sustained plateau. Considering the Ca2+ sensitivity of cAMP accumulation in these cells, lack of oscillations in [cAMP] during the initial phases of CaR stimulation was puzzling. Additional experiments showed that low-frequency, long-duration Ca2+ oscillations generated a dynamic staircase pattern in [cAMP], whereas higher frequency spiking had no effect. Our data suggest that the cAMP machinery in HEK cells acts as a low-pass filter disregarding the relatively rapid Ca2+ spiking stimulated by Ca2+-mobilizing agonists under physiological conditions
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