Warming temperatures and smaller body sizes : synchronous changes in growth of North Sea fishes

Funded by Marine Scotland SciencePeer reviewedPostprin

FIS workshop on Global synthesis of climate impacts on fish distribution and growth and implications for Scottish fisheries : FIS028

All workshop attendees and remote participants (identified in Table 1) are thanked for their contributions to presentations, discussion and this report. A. Audzijonyte, R. Allman, B. Bogstad, C. Champion, T. Essington, M. Haltuch, A. Haynie, T. Helser, E. Hjörleifsson, J. Morrongiello, M. Peck, G. Pecl, J. Pinnegar, M. Pinsky, C. Stawitz, B. Townhill, J. Thorson, and P.D. van Denderen contributed text to this report. George R. West is thanked for his participation in the public event. Jens Rasmussen assisted in the development of recommendations for future research. The assistance of Mindfully Wired Communications (Harriet Yates and Ginny Russell) is gratefully acknowledged.Publisher PD

Antarctic Ocean and Sea Ice Response to Ozone Depletion: A Two-Time-Scale Problem

The response of the Southern Ocean to a repeating seasonal cycle of ozone loss is studied in two coupled climate models and is found to comprise both fast and slow processes. The fast response is similar to the interannual signature of the southern annular mode (SAM) on sea surface temperature (SST), onto which the ozone hole forcing projects in the summer. It comprises enhanced northward Ekman drift, inducing negative summertime SST anomalies around Antarctica, earlier sea ice freeze-up the following winter, and northward expansion of the sea ice edge year-round. The enhanced northward Ekman drift, however, results in upwelling of warm waters from below the mixed layer in the region of seasonal sea ice. With sustained bursts of westerly winds induced by ozone hole depletion, this warming from below eventually dominates over the cooling from anomalous Ekman drift. The resulting slow time-scale response (years to decades) leads to warming of SSTs around Antarctica and ultimately a reduction in sea ice cover year-round. This two-time-scale behavior—rapid cooling followed by slow but persistent warming—is found in the two coupled models analyzed: one with an idealized geometry and the other with a complex global climate model with realistic geometry. Processes that control the time scale of the transition from cooling to warming and their uncertainties are described. Finally the implications of these results are discussed for rationalizing previous studies of the effect of the ozone hole on SST and sea ice extent.United States. National Aeronautics and Space Administration. Modeling, Analysis, and Prediction Program (Grant)National Science Foundation (U.S.) (Frontiers in Earth System Dynamics Project

Polar mesoscale cyclones in the northeast Atlantic: Comparing climatologies from ERA-40 and satellite imagery

Polar mesoscale cyclones over the subarctic are thought to be an important component of the coupled atmosphere–ocean climate system. However, the relatively small scale of these features presents some concern as to their representation in the meteorological reanalysis datasets that are commonly used to drive ocean models. Here polar mesocyclones are detected in the 40-Year European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis dataset (ERA-40) in mean sea level pressure and 500-hPa geopotential height, using an automated cyclone detection algorithm. The results are compared to polar mesocyclones detected in satellite imagery over the northeast Atlantic, for the period October 1993–September 1995. Similar trends in monthly cyclone numbers and a similar spatial distribution are found. However, there is a bias in the size of cyclones detected in the reanalysis. Up to 80% of cyclones larger than 500 km are detected in MSL pressure, but this hit rate decreases, approximately linearly, to ∼40% for 250-km-scale cyclones and to ∼20% for 100-km-scale cyclones. Consequently a substantial component of the associated air–sea fluxes may be missing from the reanalysis, presenting a serious shortcoming when using such reanalysis data for ocean modeling simulations. Eight maxima in cyclone density are apparent in the mean sea level pressure, clustered around synoptic observing stations in the northeast Atlantic. They are likely spurious, and a result of unidentified shortcomings in the ERA-40 data assimilation procedure

High Resolution Doppler Imager observations of ozone in the mesosphere and lower thermosphere

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95237/1/jgrd9497.pd

Oral prion neuroinvasion occurs independently of PrPC expression in the gut epithelium

The early replication of certain prion strains within Peyer’s patches in the small intestine is essential for the efficient spread of disease to the brain after oral exposure. Our data show that orally acquired prions utilize specialized gut epithelial cells known as M cells to enter Peyer’s patches. M cells express the cellular isoform of the prion protein, PrPC, and this may be exploited by some pathogens as an uptake receptor to enter Peyer’s patches. This suggested that PrPC might also mediate the uptake and transfer of prions across the gut epithelium into Peyer’s patches in order to establish infection. Furthermore, the expression level of PrPC in the gut epithelium could influence the uptake of prions from the lumen of the small intestine. To test this hypothesis, transgenic mice were created in which deficiency in PrPC was specifically restricted to epithelial cells throughout the lining of the small intestine. Our data clearly show that efficient prion neuroinvasion after oral exposure occurred independently of PrPC expression in small intestinal epithelial cells. The specific absence of PrPC in the gut epithelium did not influence the early replication of prions in Peyer’s patches or disease susceptibility. Acute mucosal inflammation can enhance PrPC expression in the intestine, implying the potential to enhance oral prion disease pathogenesis and susceptibility. However, our data suggest that the magnitude of PrPC expression in the epithelium lining the small intestine is unlikely to be an important factor which influences the risk of oral prion disease susceptibility. IMPORTANCE The accumulation of orally acquired prions within Peyer’s patches in the small intestine is essential for the efficient spread of disease to the brain. Little is known of how the prions initially establish infection within Peyer’s patches. Some gastrointestinal pathogens utilize molecules, such as the cellular prion protein PrPC, expressed on gut epithelial cells to enter Peyer’s patches. Acute mucosal inflammation can enhance PrPC expression in the intestine, implying the potential to enhance oral prion disease susceptibility. We used transgenic mice to determine whether the uptake of prions into Peyer’s patches was dependent upon PrPC expression in the gut epithelium. We show that orally acquired prions can establish infection in Peyer’s patches independently of PrPC expression in gut epithelial cells. Our data suggest that the magnitude of PrPC expression in the epithelium lining the small intestine is unlikely to be an important factor which influences oral prion disease susceptibility

A Search for Exozodiacal Clouds with Kepler

Planets embedded within dust disks may drive the formation of large scale clumpy dust structures by trapping dust into resonant orbits. Detection and subsequent modeling of the dust structures would help constrain the mass and orbit of the planet and the disk architecture, give clues to the history of the planetary system, and provide a statistical estimate of disk asymmetry for future exoEarth-imaging missions. Here we present the first search for these resonant structures in the inner regions of planetary systems by analyzing the light curves of hot Jupiter planetary candidates identified by the Kepler mission. We detect only one candidate disk structure associated with KOI 838.01 at the 3-sigma confidence level, but subsequent radial velocity measurements reveal that KOI 838.01 is a grazing eclipsing binary and the candidate disk structure is a false positive. Using our null result, we place an upper limit on the frequency of dense exozodi structures created by hot Jupiters. We find that at the 90% confidence level, less than 21% of Kepler hot Jupiters create resonant dust clumps that lead and trail the planet by ~90 degrees with optical depths >~5*10^-6, which corresponds to the resonant structure expected for a lone hot Jupiter perturbing a dynamically cold dust disk 50 times as dense as the zodiacal cloud.Comment: 22 pages, 6 figures, Accepted for publication in Ap

Is oxygen limitation in warming waters a valid mechanism to explain decreased body sizes in aquatic ectotherms?

The authors would like to acknowledge funding from Australian Research Council (grant No. DP170104240) and the Kone Foundation (to AA), Horizon 2020 European research projects ClimeFish (grant No. 677039) (to ARB) and Australian Academy of Science (to JRM)Peer reviewedPostprintPostprin

Influence of inflammatory polyarthritis on quantitative heel ultrasound measurements.

BACKGROUND: There are few data concerning the impact of inflammatory polyarthritis (IP) on quantitative heel ultrasound (QUS) measurements. The aims of this analysis were i) to determine the influence of IP on QUS measurements at the heel and, ii) among those with IP to determine the influence of disease related factors on these measurements. METHODS: Men and women aged 16 years and over with recent onset IP were recruited to the Norfolk Arthritis Register (NOAR). Individuals with an onset of joint symptoms between 1989 and 1999 were included in this analysis. At the baseline visit subjects underwent a standardised interview and clinical examination with blood taken for rheumatoid factor. A population-based prospective study of chronic disease (EPIC-Norfolk) independently recruited men and women aged 40 to 79 years from the same geographic area between 1993 and 1997. At a follow up assessment between 1998 and 2000 subjects in EPIC-Norfolk were invited to have quantitative ultrasound measurements of the heel (CUBA-Clinical) performed. We compared speed of sound (SOS) and broadband ultrasound attenuation (BUA), in those subjects recruited to NOAR who had ultrasound measurements performed (as part of EPIC-Norfolk) subsequent to the onset of joint symptoms with a group of age and sex matched non-IP controls who had participated in EPIC-Norfolk. Fixed effect linear regression was used to explore the influence of IP on the heel ultrasound parameters (SOS and BUA) so the association could be quantified as the mean difference in BUA and SOS between cases and controls. In those with IP, linear regression was used to examine the association between these parameters and disease related factors. RESULTS: 139 men and women with IP and 278 controls (mean age 63.2 years) were studied. Among those with IP, mean BUA was 76.3 dB/MHz and SOS 1621.8 m/s. SOS was lower among those with IP than the controls (difference = -10.0; 95% confidence interval (CI) -17.4, -2.6) though BUA was similar (difference = -1.2; 95% CI -4.5, +2.1). The difference in SOS persisted after adjusting for body mass index and steroid use. Among those with IP, disease activity as determined by the number of swollen joints at baseline, was associated with a lower SOS. In addition SOS was lower in the subgroup that satisfied the 1987 ACR criteria. By contrast, disease duration, steroid use and HAQ score were not associated with either BUA or SOS. CONCLUSIONS: In this general population derived cohort of individuals with inflammatory polyarthritis there is evidence from ultrasound of a potentially adverse effect on the skeleton. The effect appears more marked in those with active disease.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are