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Flux emergence at different spatial scales and with different amounts of flux has been studied using radiative magnetohydrodynamics (rMHD) simulations. We use the radiative MHD code MURaM to simulate the emergence of an untwisted magnetic flux tube of ephemeral region scale with a density nonuniformity into a background atmosphere with a small unipolar open field. We find that the tube rises to the photosphere, forming complex loop structures seen in synthetic Atmospheric Imaging Assembly(AIA) 171 Å images. The atmosphere reaches 105K at 3Mm above the surface. Our simulation provides a reference example of a less twisted ephemeral region emergence and the atmospheric response.
Cross-species evidence suggests that the ability to exert control over a stressor is a key dimension of stress exposure that may sensitize frontostriatal-amygdala circuitry to promote more adaptive responses to subsequent stressors. The present study examined neural correlates of stressor controllability in young adults. Participants (N = 56; Mage = 23.74, range = 18–30 years) completed either the controllable or uncontrollable stress condition of the first of two novel stressor controllability tasks during functional magnetic resonance imaging (fMRI) acquisition. Participants in the uncontrollable stress condition were yoked to age- and sex-matched participants in the controllable stress condition. All participants were subsequently exposed to uncontrollable stress in the second task, which is the focus of fMRI analyses reported here. A whole-brain searchlight classification analysis revealed that patterns of activity in the right dorsal anterior insula (dAI) during subsequent exposure to uncontrollable stress could be used to classify participants' initial exposure to either controllable or uncontrollable stress with a peak of 73% accuracy. Previous experience of exerting control over a stressor may change the computations performed within the right dAI during subsequent stress exposure, shedding further light on the neural underpinnings of stressor controllability.
Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
Diet has a major influence on the composition and metabolic output of the gut microbiome. Higher-protein diets are often recommended for older consumers; however, the effect of high-protein diets on the gut microbiota and faecal volatile organic compounds (VOC) of elderly participants is unknown. The purpose of the study was to establish if the faecal microbiota composition and VOC in older men are different after a diet containing the recommended dietary intake (RDA) of protein compared with a diet containing twice the RDA (2RDA). Healthy males (74⋅2 (sd 3⋅6) years; n 28) were randomised to consume the RDA of protein (0⋅8 g protein/kg body weight per d) or 2RDA, for 10 weeks. Dietary protein was provided via whole foods rather than supplementation or fortification. The diets were matched for dietary fibre from fruit and vegetables. Faecal samples were collected pre- and post-intervention for microbiota profiling by 16S ribosomal RNA amplicon sequencing and VOC analysis by head space/solid-phase microextraction/GC-MS. After correcting for multiple comparisons, no significant differences in the abundance of faecal microbiota or VOC associated with protein fermentation were evident between the RDA and 2RDA diets. Therefore, in the present study, a twofold difference in dietary protein intake did not alter gut microbiota or VOC indicative of altered protein fermentation.
An outbreak of mumps within a student population in Scotland was investigated to assess the effect of previous vaccination on infection and clinical presentation, and any genotypic variation. Of the 341 cases, 79% were aged 18–24. Vaccination status was available for 278 cases of whom 84% had received at least one dose of mumps containing vaccine and 62% had received two. The complication rate was 5·3% (mainly orchitis), and 1·2% were admitted to hospital. Genetic sequencing of mumps virus isolated from cases across Scotland classified 97% of the samples as genotype G. Two distinct clusters of genotype G were identified, one circulating before the outbreak and the other thereafter, suggesting the virus that caused this outbreak was genetically different from the previously circulating virus. Whilst the poor vaccine effectiveness we found may be due to waning immunity over time, a contributing factor may be that the current mumps vaccine is less effective against some genotypes. Although the general benefits of the measles–mumps–rubella (MMR) vaccine should continue to be promoted, there may be value in reassessing the UK vaccination schedule and the current mumps component of the MMR vaccine.
Congenital airway obstruction is rare but potentially fatal. We developed a complex airways interventional delivery team to manage such cases. Antenatal imaging detects airway compromise at an early stage and facilitates the planning of delivery procedures (‘ex utero intrapartum treatment’ and ‘operation on placental support’) which maintain feto-placental circulation whilst an airway is secured.
Method:
A retrospective review was performed of cases in which ENT input was required at birth for airway obstruction.
Results:
Four neonates were delivered before implementation of the service: two were intubated and another two underwent tracheostomy but died in the peri-natal period. Seven neonates were delivered after implementation of the service: six were intubated and one underwent immediate tracheostomy. Five subsequently underwent tracheostomy (three have since been decannulated). One child with multiple congenital anomalies died due to respiratory failure. Airway obstruction was caused by lymphatic malformation, teratoma, costo-craniomandibular syndrome and choristoma.
Conclusion:
In the absence of other anomalies, interventional airway delivery led to reduced mortality and improved outcomes.
Listeria monocytogenes is a foodborne pathogen that can cause bacteraemia, meningitis, and complications during pregnancy. In July 2012, molecular subtyping identified indistinguishable L. monocytogenes isolates from six patients and two samples of different cut and repackaged cheeses. A multistate outbreak investigation was initiated. Initial analyses identified an association between eating soft cheese and outbreak-related illness (odds ratio 17·3, 95% confidence interval 2·0–825·7) but no common brand. Cheese inventory data from locations where patients bought cheese and an additional location where repackaged cheese yielded the outbreak strain were compared to identify cheeses for microbiological sampling. Intact packages of imported ricotta salata yielded the outbreak strain. Fourteen jurisdictions reported 22 cases from March–October 2012, including four deaths and a fetal loss. Six patients ultimately reported eating ricotta salata; another reported eating cheese likely cut with equipment also used for contaminated ricotta salata, and nine more reported eating other cheeses that might also have been cross-contaminated. An FDA import alert and US and international recalls followed. Epidemiology-directed microbiological testing of suspect cheeses helped identify the outbreak source. Cross-contamination of cheese highlights the importance of using validated disinfectant protocols and routine cleaning and sanitizing after cutting each block or wheel.
Nitrous oxide (N2O) emissions associated with urine nitrogen (N) deposition during grazing are a major component of greenhouse gas emissions from domestic livestock. The present study investigated the relationship between urine N loading rate and the efficacy of a nitrification inhibitor, dicyandiamide (DCD), on cumulative N2O emissions from a grassland soil in Ireland over 80 and 360-day periods in 2009/10 and 2010/11. A diminishing curvilinear relationship between urine N rate and cumulative N2O emissions was observed in both years. Despite this increase in cumulative N2O emissions, the emission factor (EF3) for N2O decreased with increasing urine N rate from, on average, 0·24 to 0·10% (urine applied at 300 and 1000 kg N/ha, respectively), during an 80-day measurement period. This was probably the result of a factor other than N, such as carbon (C), limiting the production of N2O. The efficacy of DCD varied with urine N loading rate, and inter-annual variability in efficacy was also observed. Dicyandiamide was effective at reducing N2O production for 50–80 days after urine application, which accounted for the major period of elevated daily flux. However, DCD was ineffective at reducing N2O production after this period, which was likely a result of its removal from the soil via degradation and leaching.
We observed with HARPS, the Rossiter-McLaughlin effect for 40 of the 75 transiting hot Jupiters discovered in the Southern Hemisphere by WASP. Our observations reveal a wide distribution in orbital inclinations indicative of past dynamical interactions. Our data also demonstrate the important effect produced by tidal interactions in shaping the spin–orbit (β) angle distribution. We briefly present and interpret the data we collected in a series of graphs.
The Australian Square Kilometre Array Pathfinder (ASKAP) will give us an unprecedented opportunity to investigate the transient sky at radio wavelengths. In this paper we present VAST, an ASKAP survey for Variables and Slow Transients. VAST will exploit the wide-field survey capabilities of ASKAP to enable the discovery and investigation of variable and transient phenomena from the local to the cosmological, including flare stars, intermittent pulsars, X-ray binaries, magnetars, extreme scattering events, interstellar scintillation, radio supernovae, and orphan afterglows of gamma-ray bursts. In addition, it will allow us to probe unexplored regions of parameter space where new classes of transient sources may be detected. In this paper we review the known radio transient and variable populations and the current results from blind radio surveys. We outline a comprehensive program based on a multi-tiered survey strategy to characterise the radio transient sky through detection and monitoring of transient and variable sources on the ASKAP imaging timescales of 5 s and greater. We also present an analysis of the expected source populations that we will be able to detect with VAST.
A heuristic greedy algorithm is developed for efficiently tiling spatially dense redshift surveys. In its first application to the Galaxy and MassAssembly (GAMA) redshift survey we find it rapidly improves the spatial uniformity of our data, and naturally corrects for any spatial bias introduced by the 2dF multi-object spectrograph. We make conservative predictions for the final state of the GAMA redshift survey after our final allocation of time, and can be confident that even if worse than typical weather affects our observations, all of our main survey requirements will be met.
In laboratory experiments adults and nymphs of the western conifer seed bug, Leptoglossus occidentalis Heidemann, were allowed to feed on mature seeds of Douglas-fir, Pseudotsuga menziesii (Mirbel) Franco. Weight-loss measurements and scanning electron microscopy provided strong supporting evidence for the use of simple radiographic diagnosis as a method of classifying feeding damage to seeds into four categories: light (greater than two thirds of seed contents remaining), moderate (one third to two thirds of seed contents remaining), severe (less than one third of seed contents remaining), and extreme (seed empty). Scanning electron micrographs showed the apparent depletion of lipid and protein storage reserves which was verified by quantitative analyses that showed significant loss of lipid and buffer-insoluble (crystalloid) storage protein from seeds in all damage categories. The amount of buffer-soluble (matrix) protein was reduced in seeds from the severe and extreme damage categories. The increase in buffer-soluble protein observed in lightly damaged seeds was likely due to the solubilization of crystalloid storage protein, as a result of its breakdown into smaller peptides. Our results suggest that through the action of both lipases and proteases, L. occidentalis can have a serious impact on the major storage reserves of conifer seeds. Moreover, our data suggest that L. occidentalis feeds in a different manner than the laceration and flushing method found in other seed-feeding Hemiptera.