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The Lunar Environment heliospheric X-ray Imager (LEXI) and Solar wind Magnetosphere Ionosphere Link Explorer (SMILE) missions will image the Earth’s dayside magnetopause and cusps in soft X-rays after their respective launches in the near future, to specify global magnetic reconnection modes for varying solar wind conditions. To support the success of these scientific missions, it is critical to develop techniques that extract the magnetopause locations from the observed soft X-ray images. In this research, we introduce a new geometric equation that calculates the subsolar magnetopause position (\begin{document}$ {R}_{\mathrm{s}} $\end{document}) from a satellite position, the look direction of the instrument, and the angle at which the X-ray emission is maximized. Two assumptions are used in this method: (1) The look direction where soft X-ray emissions are maximized lies tangent to the magnetopause, and (2) the magnetopause surface near the subsolar point is almost spherical and thus \begin{document}$ {R}_{\mathrm{s}} $\end{document} is nearly equal to the radius of the magnetopause curvature. We create synthetic soft X-ray images by using the Open Geospace General Circulation Model (OpenGGCM) global magnetohydrodynamic model, the galactic background, the instrument point spread function, and Poisson noise. We then apply the fast Fourier transform and Gaussian low-pass filters to the synthetic images to remove noise and obtain accurate look angles for the soft X-ray peaks. From the filtered images, we calculate \begin{document}$ {R}_{\mathrm{s}} $\end{document} and its accuracy for different LEXI locations, look directions, and solar wind densities by using the OpenGGCM subsolar magnetopause location as ground truth. Our method estimates \begin{document}$ {R}_{\mathrm{s}} $\end{document} with an accuracy of \begin{document}$ {10\;\mathrm{c}\mathrm{m}}^{-3} $\end{document}. The accuracy improves for greater solar wind densities and during southward interplanetary magnetic fields. The method captures the magnetopause motion during southward interplanetary magnetic field turnings. Consequently, the technique will enable quantitative analysis of the magnetopause motion and help reveal the dayside reconnection modes for dynamic solar wind conditions. This technique will support the LEXI and SMILE missions in achieving their scientific objectives.

The Soft X-ray Imager (SXI) is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer (SMILE) mission. SMILE is a joint science mission between the European Space Agency (ESA) and the Chinese Academy of Sciences (CAS) and is due for launch in 2025. SXI is a compact X-ray telescope with a wide field-of-view (FOV) capable of encompassing large portions of Earth’s magnetosphere from the vantage point of the SMILE orbit. SXI is sensitive to the soft X-rays produced by the Solar Wind Charge eXchange (SWCX) process produced when heavy ions of solar wind origin interact with neutral particles in Earth’s exosphere. SWCX provides a mechanism for boundary detection within the magnetosphere, such as the position of Earth’s magnetopause, because the solar wind heavy ions have a very low density in regions of closed magnetic field lines. The sensitivity of the SXI is such that it can potentially track movements of the magnetopause on timescales of a few minutes and the orbit of SMILE will enable such movements to be tracked for segments lasting many hours. SXI is led by the University of Leicester in the United Kingdom (UK) with collaborating organisations on hardware, software and science support within the UK, Europe, China and the United States.

Much of what we know about the solar wind’s interaction with the Earth’s magnetosphere has been gained from isolated in-situ measurements by single or multiple spacecraft. Based on their observations, we know that reconnection, whether on the dayside magnetopause or deep within the Earth’s magnetotail, controls the bulk flow of solar wind energy into and through the global system and that nightside activity provides the energized particles that power geomagnetic storms. But by their very nature these isolated in-situ measurements cannot provide an instantaneous global view of the entire system or its cross-scale dynamics. To fully quantify the dynamics of the coupled solar wind-magnetosphere requires comprehensive end-to-end global imaging of the key plasma structures that comprise the magnetosphere which have spatial resolutions that exceeds anything possible with multi-point or constellation situ measurements. Global, end-to-end, imaging provides the pathway to understanding the system as a whole, its constituent parts, and its cross-scale processes on a continuous basis, as needed to quantify the flow of solar wind energy through the global magnetospheric system. This paper describes how a comprehensively-instrumented single spacecraft in a high-altitude, high-inclination orbit coupled with ground-based instruments provides the essential observations needed to track and quantify the flow of solar wind energy through the magnetosphere. This includes observations of the solar wind plasma and magnetic field input, the magnetopause location in soft X-rays, the auroral oval in far ultraviolet, the ring current in energetic neutrals, the plasmasphere in extreme ultraviolet, the exosphere in Lyman-α, and the microstructure of the nightside auroral oval from ground-based all sky cameras.

Abstract Flexible electronic skin with features that include sensing, processing, and responding to stimuli have transformed human–robot interactions. However, more advanced capabilities, such as human‐like self‐protection modalities with a sense of pain, sign of injury, and healing, are more challenging. Herein, a novel, flexible, and robust diffusive memristor based on a copolymer of chlorotrifluoroethylene and vinylidene fluoride (FK‐800) as an artificial nociceptor (pain sensor) is reported. Devices composed of Ag/FK‐800/Pt have outstanding switching endurance >106 cycles, orders of magnitude higher than any other two‐terminal polymer/organic memristors in literature (typically 102–103 cycles). In situ conductive atomic force microscopy is employed to dynamically switch individual filaments, which demonstrates that conductive filaments correlate with polymer grain boundaries and FK‐800 has superior morphological stability under repeated switching cycles. It is hypothesized that the high thermal stability and high elasticity of FK‐800 contribute to the stability under local Joule heating associated with electrical switching. To mimic biological nociceptors, four signature nociceptive characteristics are demonstrated: threshold triggering, no adaptation, relaxation, and sensitization. Lastly, by integrating a triboelectric generator (artificial mechanoreceptor), memristor (artificial nociceptor), and light emitting diode (artificial bruise), the first bioinspired injury response system capable of sensing pain, showing signs of injury, and healing, is demonstrated.

Feedback from star formation may play a key role in energizing the hot, diffuse, X-ray emitting circumgalactic medium (CGM). We observed the diffuse hot gas on the interior of the Orion–Eridanus Superbubble (OES) produced by feedback from the Orion OB association. Using HaloSat, a CubeSat X-ray observatory, we cover the majority of the OES using 11 HaloSat fields, each with a 10° diameter. We find the gas is well described by two thermal plasma components. There are regions of enhanced emission measure (EM) that coincide with the Eridanus X-ray Enhancement and the Orion OB association. Individual field temperatures are statistically consistent with the weighted average of all of the OES fields: a warm temperature k T _w = 0.17 ± 0.02 keV and a hot temperature k T _h = 0.79 ± 0.12 keV. The gas is overpressured in comparison with typical interstellar medium pressures, and the rate of energy injected by Orion OB1 can sufficiently power growth of the superbubble. The gas’s radiative cooling timescale (∼30 Myr) is long in comparison with the rate of hot gas production. The temperatures and EMs of the gas agree with properties of the bulk CGM elsewhere in the Milky Way. If we take the OES as a typical superbubble, these factors together suggest that the hot CGM is energized by star formation activity.

Products containing cannabidiol (CBD) have proliferated after the 2018 Farm Bill legalized hemp (cannabis with ≤0.3% delta-9-tetrahydrocannabinol (Δ9-THC)). CBD-containing topical products have surged in popularity, but controlled clinical studies on them are limited. This study characterized the effects of five commercially available hemp-derived high CBD/low Δ9-THC topical products. Healthy adults (N = 46) received one of six study drugs: a CBD-containing cream (N = 8), lotion (N = 8), patch (N = 7), balm (N = 8), gel (N = 6) or placebo (N = 9; matched to an active formulation). The protocol included three phases conducted over 17 days: (i) an acute drug application laboratory session, (ii) a 9-day outpatient phase with twice daily product application (visits occurred on Days 2, 3, 7 and 10) (iii) a 1-week washout phase. In each phase, whole blood, oral fluid and urine specimens were collected and analyzed via liquid chromatography with tandem mass spectrometry (LC-MS-MS) for CBD, Δ9-THC and primary metabolites of each and pharmacodynamic outcomes (subjective, cognitive/psychomotor and physiological effects) were assessed. Transdermal absorption of CBD was observed for three active products. On average, CBD/metabolite concentrations peaked after 7-10 days of product use and were highest for the lotion, which contained the most CBD and a permeation enhancer (vitamin E). Δ9-THC/metabolites were below the limit of detection in blood for all products, and no urine samples tested "positive" for cannabis using current US federal workplace drug testing criteria (immunoassay cut-off of 50 ng/mL and confirmatory LC-MS-MS cut-off of 15 ng/mL). Unexpectedly, nine participants (seven lotions, one patch and one gel) exhibited Δ9-THC oral fluid concentrations ≥2 ng/mL (current US federal workplace threshold for a "positive" test). Products did not produce discernable pharmacodynamic effects and were well-tolerated. This study provides important initial data on the acute/chronic effects of hemp-derived topical CBD products, but more research is needed given the diversity of products in this market., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Traditionally, smoking has been the predominant method for administering cannabis, but alternative routes of administration have become more prevalent. Additionally, research examining urinary cannabinoid excretion profiles has primarily focused on 11-nor-9-carboxy-∆9-tetrahydrocannabinol (∆9-THC-COOH), a metabolite of ∆9-tetrahydrocannabinol (∆9-THC), as the primary analyte. The aim of the current study was to characterize the urinary excretion profile of ∆9-THC-COOH, ∆9-THC, ∆8-tetrahydrocannabinol (∆8-THC), 11-hydroxy-∆9-tetrahydrocannabinol (11-OH-∆9-THC), ∆9-tetrahydrocannabivarin (THCV), 11-nor-∆9-tetrahydrocannabivarin-9-carboxlic acid (THCV-COOH), cannabidiol (CBD), cannabinol (CBN) and 8,11-dihydroxytetrahydrocannabinol (8,11-diOH-∆9-THC) following controlled administration of both oral and vaporized cannabis. Participants (n = 21, 11 men/10 women) who were infrequent cannabis users ingested cannabis-containing brownies (0, 10 and 25 mg ∆9-THC) and inhaled vaporized cannabis (0, 5 and 20 mg ∆9-THC) across six double-blind outpatient sessions. Urinary concentrations of ∆9-THC analytes were measured at baseline and for 8 h after cannabis administration. Sensitivity, specificity and agreement between the three immunoassays (IAs) for ∆9-THC-COOH (cutoffs of 20, 50 and 100 ng/mL) and liquid chromatography-tandem mass spectrometry (LC-MS-MS) analyses (confirmatory cutoff concentrations of 15 ng/mL) were assessed. Urinary concentrations for ∆9-THC-COOH, ∆9-THC, 11-OH-∆9-THC, THCV, CBN and 8,11-diOH-∆9-THC all peaked at 5-6 h and 4 h following oral and vaporized cannabis administration, respectively. At each active dose, median maximum concentrations (Cmax) for detected analytes were quantitatively higher after oral cannabis administration compared to vaporized. Using current recommended federal workplace drug-testing criteria (screening via IA with a cutoff of ≥50 ng/mL and confirmation via LC-MS-MS at a cutoff of ≥15 ng/mL), urine specimens tested positive for ∆9-THC-COOH in 97.6% of oral sessions and 59.5% of vaporized sessions with active ∆9-THC doses. These data indicate that while ∆9-THC-COOH may serve as the most consistent confirmatory analyte under the current drug-testing guidelines, future work examining 11-OH-∆9-THC under similar parameters could yield an alternative analyte that may be helpful in distinguishing between licit and illicit cannabis products., (Published by Oxford University Press 2022. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a class of chemicals widely used in industrial applications due to their exceptional properties and stability. However, they do not readily degrade in the environment and are linked to contamination and adverse health effects in humans and wildlife. To find alternatives for the most commonly used PFAS molecules that maintain their desirable chemical properties but are not adverse to biological lifeforms, a novel approach based upon machine learning is utilized. The machine learning model is trained on an existing set of PFAS molecules to generate over 260,000 novel PFAS molecules, which we dub PFAS-AI-Gen. Using molecular descriptors with known relationships to toxicity and industrial suitability followed by molecular docking and molecular dynamics simulations, this set of molecules is screened. In this manner, increasingly complex calculations are performed only for candidate molecules that are most likely to yield the desired properties of low binding affinity toward two selected protein receptors, the human pregnane x receptor (hPXR) and peroxisome proliferator-activated receptor γ (PPAR-γ), and high industrial suitability, defined by critical micelle concentration (CMC). The selection criteria of low binding affinity and high industrial suitability are relative to the popular PFAS alternative GenX. hPXR and PPAR-γ are selected as they are PFAS targets and facilitate a variety of functions, such as drug metabolism and glucose regulation, respectively. Through this approach, 22 promising new PFAS substitutes that may warrant experimental investigation are identified. This integrated approach of molecular screening and toxicity estimation may be applicable to other chemical classes.

The market for products containing cannabidiol (CBD) is booming globally. However, the pharmacokinetics of CBD in different oral formulations and the impact of CBD use on urine drug testing outcomes for cannabis (e.g., 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (Δ9-THCCOOH)) are understudied. This study characterized the urinary pharmacokinetics of CBD (100 mg) following vaporization or oral administration (including three formulations: gelcap, pharmacy-grade syrup and or Epidiolex) as well as vaporized CBD-dominant cannabis (containing 100 mg CBD and 3.7 mg Δ9-THC) in healthy adults (n = 18). A subset of participants (n = 6) orally administered CBD syrup following overnight fasting (versus low-fat breakfast). Urine specimens were collected before and for 58 h after dosing on a residential research unit. Immunoassay (IA) screening (cutoffs: 20, 50 and 100 ng/mL) for Δ9-THCCOOH was performed, and quantitation of cannabinoids was completed via LC-MS-MS. Urinary CBD concentrations (ng/mL) were higher after oral (mean Cmax: 734; mean Tmax: 4.7 h, n = 18) versus vaporized CBD (mean Cmax: 240; mean Tmax: 1.3 h, n = 18), and oral dose formulation significantly impacted mean Cmax (Epidiolex = 1,274 ng/mL, capsule = 776 ng/mL, syrup = 151 ng/mL, n = 6/group) with little difference in Tmax. Overnight fasting had limited impact on CBD excretion in urine, and there was no evidence of CBD conversion to Δ8- or Δ9-THC in any route or formulation in which pure CBD was administered. Following acute administration of vaporized CBD-dominant cannabis, 3 of 18 participants provided a total of six urine samples in which Δ9-THCCOOH concentrations ≥15 ng/mL. All six specimens screened positive at a 20 ng/mL IA cutoff, and two of six screened positive at a 50 ng/mL cutoff. These data show that absorption/elimination of CBD is impacted by drug formulation, route of administration and gastric contents. Although pure CBD is unlikely to impact drug testing, it is possible that hemp products containing low amounts of Δ9-THC may produce a cannabis-positive urine drug test., (© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)