Effects of Cannabidiol Ingestion on Thermoregulatory and Inflammatory Responses to Treadmill Exercise in the Heat in Recreationally Active Males.

PURPOSE: Exertional heat stress can induce systemic endotoxin exposure and a pro-inflammatory cascade, likely impairing thermoregulation. Cannabidiol (CBD) is protective in pre-clinical models of tissue ischaemia and inflammation. Therefore, this study examined the effects of CBD ingestion on exercise-induced thermoregulatory and inflammatory responses. METHODS: In a randomised, double-blinded study, thirteen active males (age 25 ± 5 y; peak oxygen uptake [V̇O2peak] 50.4 ± 3.2 mL/kg/min) ingested 298 mg CBD or placebo 105 minutes before 1 h treadmill exercise (60-65% V̇O2peak) in 32 °C and 50% relative humidity. Core temperature, skin temperature, heart rate, subjective outcomes and sweat loss were assessed during/after exercise. Plasma osmolality, plasma volume changes and plasma markers of intestinal damage (I-FABP), monocyte activation (CD14) and inflammatory cytokine responses (IL-6, IL-8 and TNF-α) were assessed at baseline, pre-exercise, 20- and 90-min post-exercise. RESULTS: Core temperature (∆ 1.69 ± 0.48 °C [CBD] and 1.79 ± 0.53 °C [Placebo]) and I-FABP increased during exercise, with no differences between conditions (p > 0.050). Mean (95% CI) CD14 was 1776 (463 to 3090) pg/mL greater 90 min post-exercise in placebo (p = 0.049). Median (interquartile range) peak IL-6 concentration was -0.8 (-1.1, -0.3) pg/mL less in CBD (p = 0.050), whilst the between-conditions difference in IL-6 area under curve was -113 (-172, 27) pg/mL·270 min (p = 0.054). CONCLUSIONS: CBD did not affect thermoregulation during exertional heat stress but appeared to elicit minor immunosuppressive effects, reducing CD14 and IL-6 responses, warranting investigation in humans under more severe heat strain and other pro-inflammatory scenarios.

Open-source magnetic resonance imaging: Improving access, science, and education through global collaboration.

Open-source practices and resources in magnetic resonance imaging (MRI) have increased substantially in recent years. This trend started with software and data being published open-source and, more recently, open-source hardware designs have become increasingly available. These developments towards a culture of sharing and establishing nonexclusive global collaborations have already improved the reproducibility and reusability of code and designs, while providing a more inclusive approach, especially for low-income settings. Community-driven standardization and documentation efforts are further strengthening and expanding these milestones. The future of open-source MRI is bright and we have just started to discover its full collaborative potential. In this review we will give an overview of open-source software and open-source hardware projects in human MRI research.

On-site construction of a point-of-care low-field MRI system in Africa.

PURPOSE: To describe the construction and testing of a portable point-of-care low-field MRI system on site in Africa. METHODS: All of the components to assemble a 50 mT Halbach magnet-based system, together with the necessary tools, were air-freighted from the Netherlands to Uganda. The construction steps included individual magnet sorting, filling of each ring of the magnet assembly, fine-tuning the inter-ring separations of the 23-ring magnet assembly, gradient coil construction, integration of gradient coils and magnet assembly, construction of the portable aluminum trolley and finally testing of the entire system with an open source MR spectrometer. RESULTS: With four instructors and six untrained personnel, the complete project from delivery to first image took approximately 11 days. CONCLUSIONS: An important step in translating scientific developments in the western world from high-income industrialized countries to low- and middle-income countries (LMICs) is to produce technology that can be assembled and ultimately constructed locally. Local assembly and construction are associated with skill development, low costs and jobs. Point-of-care systems have a large potential to increase the accessibility and sustainability of MRI in LMICs, and this work demonstrates that technology and knowledge transfer can be performed relatively seamlessly.

Assessing the utility of low resolution brain imaging: treatment of infant hydrocephalus.

As low-field MRI technology is being disseminated into clinical settings around the world, it is important to assess the image quality required to properly diagnose and treat a given disease and evaluate the role of machine learning algorithms, such as deep learning, in the enhancement of lower quality images. In this post hoc analysis of an ongoing randomized clinical trial, we assessed the diagnostic utility of reduced-quality and deep learning enhanced images for hydrocephalus treatment planning. CT images of post-infectious infant hydrocephalus were degraded in terms of spatial resolution, noise, and contrast between brain and CSF and enhanced using deep learning algorithms. Both degraded and enhanced images were presented to three experienced pediatric neurosurgeons accustomed to working in low- to middle-income countries (LMIC) for assessment of clinical utility in treatment planning for hydrocephalus. In addition, enhanced images were presented alongside their ground-truth CT counterparts in order to assess whether reconstruction errors caused by the deep learning enhancement routine were acceptable to the evaluators. Results indicate that image resolution and contrast-to-noise ratio between brain and CSF predict the likelihood of an image being characterized as useful for hydrocephalus treatment planning. Deep learning enhancement substantially increases contrast-to-noise ratio improving the apparent likelihood of the image being useful; however, deep learning enhancement introduces structural errors which create a substantial risk of misleading clinical interpretation. We find that images with lower quality than is customarily acceptable can be useful for hydrocephalus treatment planning. Moreover, low quality images may be preferable to images enhanced with deep learning, since they do not introduce the risk of misleading information which could misguide treatment decisions. These findings advocate for new standards in assessing acceptable image quality for clinical use.

Powerful turbidity currents driven by dense basal layers.

Seafloor sediment flows (turbidity currents) are among the volumetrically most important yet least documented sediment transport processes on Earth. A scarcity of direct observations means that basic characteristics, such as whether flows are entirely dilute or driven by a dense basal layer, remain equivocal. Here we present the most detailed direct observations yet from oceanic turbidity currents. These powerful events in Monterey Canyon have frontal speeds of up to 7.2 m s-1, and carry heavy (800 kg) objects at speeds of ≥4 m s-1. We infer they consist of fast and dense near-bed layers, caused by remobilization of the seafloor, overlain by dilute clouds that outrun the dense layer. Seabed remobilization probably results from disturbance and liquefaction of loose-packed canyon-floor sand. Surprisingly, not all flows correlate with major perturbations such as storms, floods or earthquakes. We therefore provide a new view of sediment transport through submarine canyons into the deep-sea.

Chemistry of silica scale mitigation for RO desalination with particular reference to remote operations.

Silica scaling in reverse osmosis of groundwater is a significant issue in water stressed areas due to the limitations that scaling imposes on water recovery. While calcium and magnesium scaling potential can be significantly reduced by the use of ion exchange or other softening processes, the silica scaling potential typically remains. Improving the recovery of reverse osmosis by limiting the potential for silica scale is important in ensuring maximum water recovery. This is particularly important for mining and natural gas industries that are located in remote regions. The remote nature of these sites imposes three major restrictions on the silica scale mitigation process. Firstly, the generation of poorly dewaterable sludges must be avoided. Also, the quality of any reverse osmosis (RO) permeate must be able to meet the end use requirements, particularly for boilers. Finally, silica removal should not impact upon other potentially useful or valuable components within the brine, and should not make the disposal of the unusable waste brine components more difficult. Reduction of scaling potential can be achieved in three main ways: operating RO at high pH after hardness has been removed, operating at low pH, and reducing the silica concentration either in pretreatment or by using an interstage technique. Operating at high pH has the initial requirement of hardness removal to prevent scaling and this could be an issue on some sites. Hardness removal operations that use ion exchange resins may be challenged by water chemistry and the operational costs associated with high chemical regeneration costs. Operating at low pH may be more desirable than high pH operation as this can help to reduce the risk of scale formation from calcium or magnesium salts. The drawback comes from the cost of acid, particularly for high-alkalinity waters. There are numerous silica removal techniques including chemical dosing of lime, or aluminium or iron salts, electrocoagulation, adsorption, ion exchange and seeded precipitation. Of these, adsorption onto aluminium compounds appears to give the best results and have received the most attention where restrictions on sludge production and brine disposal common to operations in remote locations are in place. Adsorption onto iron compounds appears to occur more quickly, but leads to the formation of a hard, glass-like scale that may be more difficult to remove, making this process unattractive from the point of view of sorbent regeneration.