Investigating the location and strength of the auroral electrojets using Swarm

The auroral electrojets are a key space weather phenomenon. They are formed by horizontal Hall currents that flow within the ionospheric polar regions at an altitude of around 115 km. They form ovals around the magnetic poles but their latitudinal position, width, and strength are highly variable. These are governed by geomagnetic activity and solar wind conditions, along with a global ordering by the main magnetic field. Typically, greater geomagnetic activity will cause the electrojets to intensify and move equatorward. This is associated with greater auroral displays in more populated areas but also with potentially severe consequences both on Earth and in space: - geomagnetically Induced Currents (GICs) - disturbance to radio communications and GNSS signals - disruption to navigation applications - increased drag on satellites due to expansion of the atmosphere The auroral electrojet system can be described by the AE activity indices derived from measurements at ground-based magnetic observatories. The accuracy of the AE indices is limited by the observatories' fixed positions, which inhibits the ability to consistently locate the electrojets. Significantly, the indices only cover the Northern hemisphere so do not capture the differences between the Northern and Southern systems. Polar low-Earth orbit satellite observations offer the opportunity to overcome these limitations, by providing excellent latitudinal resolution and coverage equally over both poles. There have been several demonstrations of using satellites to monitor the auroral electrojets: Olsen (1996) using Magsat; Moretto et al (2002) using Oersted, CHAMP, and SAC-C; Juusola et al. (2009) and Vennerstrom and Moretto (2013) using CHAMP; and Hamilton and Macmillan (2013) using Magsat and CHAMP. The results presented here apply the method of Vennerstrom and Moretto (2013) to data from the Swarm mission

Rapid response learning of brand logo priming:Evidence that brand priming is not dominated by rapid response learning

Repetition priming increases the accuracy and speed of responses to repeatedly processed stimuli. Repetition priming can result from two complementary sources: rapid response learning and facilitation within perceptual and conceptual networks. In conceptual classification tasks, rapid response learning dominates priming of object recognition, but it does not dominate priming of person recognition. This suggests that the relative engagement of network facilitation and rapid response learning depends on the stimulus domain. Here, we addressed the importance of the stimulus domain for rapid response learning by investigating priming in another domain, brands. In three experiments, participants performed conceptual decisions for brand logos. Strong priming was present, but it was not dominated by rapid response learning. These findings add further support to the importance of the stimulus domain for the relative importance of network facilitation and rapid response learning, and they indicate that brand priming is more similar to person recognition priming than object recognition priming, perhaps because priming of both brands and persons requires individuation. </jats:p

STarT Back Tool risk stratification is associated with changes in movement profile and sensory discrimination in low back pain: A study of 290 patients

Background: Investigation of movement and sensory profiles across STarT Back risk subgroups. Methods: A chronic low back pain cohort (n = 290) were classified as low, medium or high risk using the STarT Back Tool, and completed a repeated spinal bending task and quantitative sensory testing. Pain summation, time taken and the number of protective behaviours with repeated bending were measured. Sensory tests included two-point discrimination, temporal summation, pressure/thermal pain thresholds and conditioned pain modulation. Subgroups were profiled against movement and sensory variables. Results: The high-risk subgroup demonstrated greater pain summation following repeated forward bending (p &lt; 0.001). The medium-risk subgroup demonstrated greater pain summation following repeated backward bending (p = 0.032). Medium- and high-risk subgroups demonstrated greater forward/backward bend time compared to the low-risk subgroup (p = 0.001, p = 0.005, respectively). Medium- and high-risk subgroups demonstrated a higher number of protective behaviours per forward bend compared to the low-risk subgroup (p = 0.008). For sensory variables, only two-point discrimination differed between subgroups, with medium- and high-risk subgroups demonstrating higher thresholds (p = 0.016). Conclusions: This study showed altered movement characteristics and sensory discrimination across SBT risk subgroups in people with CLBP. Membership of the high SBT risk subgroup was associated with greater pain and disability levels, greater pain summation following repeated bending, slower bending times, a greater number of protective behaviours during forward bending, and a higher TPD threshold. Treatment outcomes for higher risk SBT subgroups may be enhanced by interventions specifically targeting movement and sensory alterations. Significance: In 290 people with chronic low back pain movement profile and two-point discrimination threshold differed across risk subgroups defined by the STarT Back Tool. Conversely, pain sensitivity did not differ across these subgroups. These findings may add further guidance for targeted care in these subgroups

Coastal iodine emissions: part 2. Chamber experiments of particle formation from Laminaria digitata-derived and laboratory-generated I2

Laboratory studies into particle formation from Laminaria digitata macroalgae were undertaken to elucidate aerosol formation for a range of I2 (0.3−76 ppbv) and O3(<3−96 ppbv) mixing ratios and light levels (EPAR = 15, 100,and 235 μmol photons m−2 s−1). No clear pattern was observed for I2 or aerosol parameters as a function of light levels. Aerosol mass fluxes and particle number concentrations,were, however, correlated with I2 mixing ratios for low O3mixing ratios of <3 ppbv (R2 = 0.7 and 0.83, respectively for low light levels, and R2 = 0.95 and 0.98, respectively for medium lightlevels). Additional experiments into particle production as a function of laboratory-generated I2, over a mixing ratio range of 1−8ppbv, were conducted under moderate O3 mixing ratios (∼24 ppbv) where a clear, 100-fold or greater, increase in the aeroso lnumber concentrations and mass fluxes was observed compared to the low O3 experiments. A linear relationship between particle concentration and I2 was found, in reasonable agreement with previous studies. Scaling the laboratory relationship to aerosol concentrations typical of the coastal boundary layer suggests a I2 mixing ratio range of 6−93 pptv can account for the observed particle production events. Aerosol number concentration produced from I2 is more than a factor of 10 higher than thatproduced from CH2I2 for the same mixing ratios

Coastal iodine emissions. 1. Release of I2 by Laminaria digitata in chamber experiments

Tidally exposed macroalgae emit large amounts of I2 and iodocarbons that produce hotspots of iodine chemistry and intense particle nucleation events in the coastal marine boundary layer. Current emission rates are poorly characterized, however,with reported emission rates varying by 3 orders of magnitude. In this study, I2 emissions from 25 Laminaria digitata samples were investigated in a simulation chamber using incoherent broadbandcavity-enhanced absorption spectroscopy (IBBCEAS). The chamber design allowed gradual extraction of seawater to simulate tidal emersion of algae. Samples were exposed to air with or without O3 and to varying irradiances. Emission of I2 occurred in four distinct stages: (1) moderate emissions from partially submerged samples;(2) a strong release by fully emerged samples; (3) slowing or stopping of I2 release; and (4) later pulses of I2 evident in some samples. Emission rates were highly variable and ranged from 7to 616 pmol min−1 gFW−1 in ozone-free air, with a median value of 55 pmol min−1 gFW−1 for 20 samples

Neurogranin in Alzheimer’s disease and ageing: a human post-mortem study

Neurogranin (Ng), a post-synaptic protein involved in memory formation, has been investigated as a biomarker in the cerebrospinal fluid (CSF) in Alzheimer's disease (AD) and ageing. CSF Ng levels are elevated in AD relative to healthy controls and correlate with cognition; however, few studies have focused on Ng abundance in the brain. Synapse loss in the brain correlates closely with cognitive decline in AD making synaptic biomarkers potentially important for tracking disease progression, but the links between synaptic protein changes in CSF and brain remain incompletely understood. In the current study, Ng abundance was examined in post-mortem human brain tissue across AD, healthy ageing (HA), and mid-life (ML) cohorts. Ng levels were quantified in three brain regions associated with cognitive change found during ageing and neurodegenerative diseases, namely the middle temporal gyrus, primary visual cortex and the posterior hippocampus using immunohistochemistry. To support immunohistochemical analysis, total homogenate and biochemically enriched synaptic fractions from available temporal gyrus tissues were examined by immunoblot. Finally, we examined whether Ng is associated with lifetime cognitive ageing. Ng levels were significantly reduced in AD relative to HA and ML cases across all regions. Additionally Ng was significantly reduced in HA in comparison to ML in the primary visual cortex. Immunoblotting confirms reduced Ng levels in AD cases supporting immunohistochemical results. Interestingly, there was also a significant reduction of synapse-associated Ng in our group who had lifetime cognitive decline in comparison to the group with lifetime cognitive resilience indicating loss of neurogranin in remaining synapses during ageing is associated with cognitive decline. Our findings indicate that increases in CSF Ng reflect loss of brain neurogranin and support the use of CSF Ng as a biomarker of AD and potentially of cognitive decline in healthy ageing

Polygenic burden in focal and generalized epilepsies.

Rare genetic variants can cause epilepsy, and genetic testing has been widely adopted for severe, paediatric-onset epilepsies. The phenotypic consequences of common genetic risk burden for epilepsies and their potential future clinical applications have not yet been determined. Using polygenic risk scores (PRS) from a European-ancestry genome-wide association study in generalized and focal epilepsy, we quantified common genetic burden in patients with generalized epilepsy (GE-PRS) or focal epilepsy (FE-PRS) from two independent non-Finnish European cohorts (Epi25 Consortium, n = 5705; Cleveland Clinic Epilepsy Center, n = 620; both compared to 20 435 controls). One Finnish-ancestry population isolate (Finnish-ancestry Epi25, n = 449; compared to 1559 controls), two European-ancestry biobanks (UK Biobank, n = 383 656; Vanderbilt biorepository, n = 49 494), and one Japanese-ancestry biobank (BioBank Japan, n = 168 680) were used for additional replications. Across 8386 patients with epilepsy and 622 212 population controls, we found and replicated significantly higher GE-PRS in patients with generalized epilepsy of European-ancestry compared to patients with focal epilepsy (Epi25: P = 1.64×10-15; Cleveland: P = 2.85×10-4; Finnish-ancestry Epi25: P = 1.80×10-4) or population controls (Epi25: P = 2.35×10-70; Cleveland: P = 1.43×10-7; Finnish-ancestry Epi25: P = 3.11×10-4; UK Biobank and Vanderbilt biorepository meta-analysis: P = 7.99×10-4). FE-PRS were significantly higher in patients with focal epilepsy compared to controls in the non-Finnish, non-biobank cohorts (Epi25: P = 5.74×10-19; Cleveland: P = 1.69×10-6). European ancestry-derived PRS did not predict generalized epilepsy or focal epilepsy in Japanese-ancestry individuals. Finally, we observed a significant 4.6-fold and a 4.5-fold enrichment of patients with generalized epilepsy compared to controls in the top 0.5% highest GE-PRS of the two non-Finnish European cohorts (Epi25: P = 2.60×10-15; Cleveland: P = 1.39×10-2). We conclude that common variant risk associated with epilepsy is significantly enriched in multiple cohorts of patients with epilepsy compared to controls-in particular for generalized epilepsy. As sample sizes and PRS accuracy continue to increase with further common variant discovery, PRS could complement established clinical biomarkers and augment genetic testing for patient classification, comorbidity research, and potentially targeted treatment

CE20008

The WESPAS survey program is the consolidation of two existing survey programs carried out by FEAS, the Malin Shelf herring acoustic survey, and the boarfish acoustic survey. The Malin Shelf herring acoustic survey has been carried out annually since 2008 and reports on the annual abundance of summer feeding aggregations of herring to the west of Scotland and the north and west of Ireland from 54°N to 58°30’N. The boarfish survey was conducted from 2011 using a chartered fishing vessel and reported the abundance of spawning aggregations of boarfish from 47°N to 57°N. In 2016 both surveys were combined into the WESPAS survey and have been carried out onboard the RV Celtic Explorer over a 42-day period, providing synoptic coverage of shelf waters from 47°30’N northwards to 58°30’N. Age stratified relative stock abundance estimates of boarfish, herring and horse mackerel within the survey area were calculated using acoustic data and biological data from trawl sampling. Stock estimates of boarfish and horse mackerel were submitted to the ICES assessment Working Group for Widely Distributed Stocks (WGWIDE) meeting in August 2020. Herring estimates are submitted to the Herring Assessment Working Group (HAWG) meeting in March every year. Survey performance will be reviewed at the ICES Planning Group meeting for International Pelagic Surveys (WGIPS) meeting in January 2021