We present an analysis of magnetic field and suprathermal electron measurements from the Mars Global Surveyor (MGS) spacecraft that reveals isolated magnetic structures filled with Martian ...atmospheric plasma located downstream from strong crustal magnetic fields with respect to the flowing solar wind. The structures are characterized by magnetic field enhancements and rotations characteristic of magnetic flux ropes, and characteristic ionospheric electron energy distributions with angular distributions distinct from surrounding regions. These observations indicate that significant amounts of atmosphere are intermittently being carried away from Mars by a bulk removal process: the top portions of crustal field loops are stretched through interaction with the solar wind and detach via magnetic reconnection. This process occurs frequently and may account for as much as 10% of the total present‐day ion escape from Mars.
Purple-pericarp sweetcorn (PPS) is a novel product, requiring both purple pigment development and maintenance of sweetness. Storage period and temperature had a profound impact on total anthocyanin ...accumulation (TAC) and sugar content. While TAC remained relatively unchanged during 14-day storage at 4 °C, the first recorded observation of continuing accumulation of anthocyanin and phenolic compounds was concurrent with an increase in purple pigment coverage across the surface of the kernel at 23 °C. TAC in PPS significantly increased, doubling after 14 days at 23 °C. Anthocyanin concentration and kernel coverage were also affected by harvest maturity. The results indicated that biosynthesis of anthocyanins is still occurring during postharvest storage of PPS. A significant decline in sugar concentration was also observed during storage with a greater decline at 23 °C. As anthocyanin accumulation and maintaining sweetness are important factors for sweetcorn, identifying storage temperatures that optimize both quality criteria are required.
Individuals with generalized social anxiety disorder (gSAD) exhibit attentional bias to salient stimuli, which is reduced in patients whose symptoms improve after treatment, indicating that ...mechanisms of bias mediate treatment success. Therefore, pre-treatment activity in regions implicated in attentional control over socio-emotional signals (e.g. anterior cingulate cortex, dorsolateral prefrontal cortex) may predict response to cognitive behavioral therapy (CBT), evidence-based psychotherapy for gSAD.
During functional magnetic resonance imaging, 21 participants with gSAD viewed images comprising a trio of geometric shapes (circles, rectangles or triangles) alongside a trio of faces (angry, fearful or happy) within the same field of view. Attentional control was evaluated with the instruction to 'match shapes', directing attention away from faces, which was contrasted with 'match faces', whereby attention was directed to emotional faces.
Whole-brain voxel-wise analyses showed that symptom improvement was predicted by enhanced pre-treatment activity in the presence of emotional face distractors in the dorsal anterior cingulate cortex and dorsal medial prefrontal cortex. Additionally, CBT success was foretold by less activity in the amygdala and/or increased activity in the medial orbitofrontal gyrus during emotion processing.
CBT response was predicted by pre-treatment activity in prefrontal regions and the amygdala. The direction of activity suggests that individuals with intact attentional control in the presence of emotional distractors, regulatory capacity over emotional faces and/or less reactivity to such faces are more likely to benefit from CBT. Findings indicate that baseline neural activity in the context of attentional control and emotion processing may serve as a step towards delineating mechanisms by which CBT exerts its effects.
Summary
Aerosol‐generating procedures such as tracheal intubation and extubation pose a potential risk to healthcare workers because of the possibility of airborne transmission of infection. Detailed ...characterisation of aerosol quantities, particle size and generating activities has been undertaken in a number of simulations but not in actual clinical practice. The aim of this study was to determine whether the processes of facemask ventilation, tracheal intubation and extubation generate aerosols in clinical practice, and to characterise any aerosols produced. In this observational study, patients scheduled to undergo elective endonasal pituitary surgery without symptoms of COVID‐19 were recruited. Airway management including tracheal intubation and extubation was performed in a standard positive pressure operating room with aerosols detected using laser‐based particle image velocimetry to detect larger particles, and spectrometry with continuous air sampling to detect smaller particles. A total of 482,960 data points were assessed for complete procedures in three patients. Facemask ventilation, tracheal tube insertion and cuff inflation generated small particles 30–300 times above background noise that remained suspended in airflows and spread from the patient’s facial region throughout the confines of the operating theatre. Safe clinical practice of these procedures should reflect these particle profiles. This adds to data that inform decisions regarding the appropriate precautions to take in a real‐world setting.
Direct ionization from low energy protons is shown to cause upsets in a 65-nm bulk CMOS SRAM, consistent with results reported for other deep submicron technologies. The experimental data are used to ...calibrate a Monte Carlo rate prediction model, which is used to evaluate the importance of this upset mechanism in typical space environments. For the ISS orbit and a geosynchronous (worst day) orbit, direct ionization from protons is a major contributor to the total error rate, but for a geosynchronous (solar min) orbit, the proton flux is too low to cause a significant number of events. The implications of these results for hardness assurance are discussed.
Abstract
The degree of specific ventilatory heterogeneity (spatial unevenness of ventilation) of the lung is a useful marker of early structural lung changes which has the potential to detect ...early-onset disease. The Inspired Sinewave Test (IST) is an established noninvasive ‘gas-distribution’ type of respiratory test capable of measuring the cardiopulmonary parameters. We developed a simulation-based optimisation for the IST, with a simulation of a realistic heterogeneous lung, namely a lognormal distribution of spatial ventilation and perfusion. We tested this method in datasets from 13 anaesthetised pigs (pre and post-lung injury) and 104 human subjects (32 healthy and 72 COPD subjects). The 72 COPD subjects were classified into four COPD phenotypes based on ‘GOLD’ classification. This method allowed IST to identify and quantify heterogeneity of both ventilation and perfusion, permitting diagnostic distinction between health and disease states. In healthy volunteers, we show a linear relationship between the ventilatory heterogeneity versus age (
$${R}^{2}=0.42$$
R
2
=
0.42
). In a mechanically ventilated pig, IST ventilatory heterogeneity in noninjured and injured lungs was significantly different (
p
< 0.0001). Additionally, measured indices could accurately identify patients with COPD (area under the receiver operating characteristic curve is 0.76,
p
< 0.0001). The IST also could distinguish different phenotypes of COPD with 73% agreement with spirometry.
Organic solar cells utilizing the small molecule donor 7,7′‐(4,4‐bis(2‐ethylhexyl)‐4H‐silolo3,2‐b:4,5‐b′dithiophene‐2,6‐diyl)bis(6‐fluoro‐4‐(5′‐hexyl‐2,2′‐bithiophen‐5‐yl)benzoc1,2,5 thiadiazole) ...(p‐DTS(FBTTh2)2 and the polymer acceptor poly{N,N′‐bis(2‐octyldodecyl)‐1,4,5,8‐naphthalenedicarboximide‐2,6‐diyl‐alt‐5,5′‐(2,2′‐bithiophene)}(P(NDI2OD‐T2)) are investigated and a power conversion efficiency of 2.1% is achieved. By systematic study of bulk heterojunction (BHJ) organic photovoltaic (OPV) quantum efficiency, film morphology, charge transport and extraction and exciton diffusion, the loss processes in this blend is revealed compared to the blend of 6,6‐phenyl‐C71‐butyric acid methyl ester (PC71BM) and the same donor. An exciton diffussion study using Förster resonant energy transfer (FRET) shows the upper limit of the P(NDI2OD‐T2) exciton diffusion length to be only 1.1 nm. The extremely low exciton diffusion length of P(NDI2OD‐T2), in combination with the overlap in donor and acceptor absorption, is then found to significantly limit device performance. These results suggest that BHJ OPV devices utilizing P(NDI2OD‐T2) as an acceptor material will likely be limited by its low exciton diffusion length compared to devices utilizing functionalized fullerene acceptors, especially when P(NDI2OD‐T2) significantly competes with the donor molecule for photon absorption.
Organic solar cells
based on a small molecule donor and the polymer acceptor P(NDI2OD‐T2) are fabricated and investigated. Through a comprehensive study of the optical and electronic properties of the blend films, the poor exciton diffusion length of P(NDI2OD‐T2) is identified as the primary cause of the poor performance. In order to make non‐fullerene acceptors competitive, the exciton diffusion length must be considered.
Ingested polyphenols from plant-based foods are in part carried to the large intestine and metabolised by resident microbiota. This work investigated the release and microbial transformation of ...polyphenols adsorbed individually or in combination to apple cell walls (ACW) and pure (bacterial) cellulose (BC). BC and ACW, representing poorly- and highly-fermentable fibre models respectively, were used to investigate influences of interactions with polyphenols (cyanidin-3-glucoside, (±)-catechin, ferulic acid), on the release and microbial metabolism of polyphenols during
in vitro
digestion and fermentation. Bound polyphenols were partially released (20-70%) during simulated digestion, depending on polyphenol molecular structure. All remaining bound polyphenols were completely released and metabolised after 6-9 h by porcine large intestine microbiota, with formation of a number of intermediates and end-products. The same pathways of polyphenol microbial metabolism were observed in the presence and absence of ACW/BC, suggesting that microbial metabolism of polyphenols and carbohydrate substrates seems likely independent. Some polyphenol metabolism products were produced faster in the presence of carbohydrate fermentation, particularly of ACW. Microbial metabolism pathways of model polyphenols by a porcine faecal inoculum are not affected by being associated with BC or ACW, but the rate of metabolism is modestly enhanced with concurrent carbohydrate fermentation.
The metabolic pathways of polyphenol degradation are not influenced by the presence of plant cell walls during
in vitro
fermentation, but co-fermentation of cell walls may lead to faster microbial metabolism of polyphenols.
We present Mars Global Surveyor measurements of bipolar out‐of‐plane magnetic fields at current sheets in Mars' magnetosphere. These signatures match predictions from simulations and terrestrial ...observations of collisionless magnetic reconnection, and could similarly indicate differential ion and electron motion and the resulting Hall current systems near magnetic X lines. Thus, these observations may represent passages through or very near reconnection diffusion regions at Mars. Out of 28 events found at 400 km altitude with well‐defined current sheet orientations, 26 have magnetic fields consistent with the expected polarities of Hall fields near diffusion regions. For these events, we find an average ratio of Hall field to main field of 0.51 ± 0.13, and an average ratio of normal to main field (reconnection rate) of 0.16 ± 0.09, consistent with terrestrial observations of reconnection. These events do not consistently correlate with the location of crustal fields or with IMF reversals, indicating that magnetic field draping alone (perhaps enhanced by high solar wind dynamic pressure) may generate current sheets capable of reconnection. For some events, we observe field‐aligned electrons that may carry parallel currents that close the Hall current loop. Electron distributions around current sheets often indicate magnetic connection to the collisional exosphere. For crossings sunward of the X line, we usually observe an electron flux minimum at the current sheet, consistent with the resulting closed magnetic structure. For crossings antisunward of the X line, we do not observe flux minima, consistent with field lines open downstream. Collisionless reconnection, if common at Mars, could represent a significant atmospheric loss process.
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