Energy Dependence Of Cosmic Ray Anisotropy

We are using the IceCube Neutrino Observatory to detect cosmic rays from the southern hemisphere. Through nine years of cosmic ray data at full potential we have recorded higher energy events more frequently and more reliably than any other experiment in either hemisphere. The higher energies recorded coincides with a significant structure change in the arrival directions of these cosmic rays compared to lower energy events. We are able to visualize the anisotropy of this energy dependency through the creation of skymaps and show the anisotropy in equatorial coordinates by fitting 1D graphs to harmonic equations. By studying the energy dependency of our data with the creation of these maps throughout the nine years, we will be able to determine the anisotropy within the southern hemisphere

Glacial flour dust storms in the Gulf of Alaska : hydrologic and meteorological controls and their importance as a source of bioavailable iron

Author Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 38 (2011): L06602, doi:10.1029/2010GL046573.Iron is an essential micronutrient that limits primary productivity in much of the ocean, including the Gulf of Alaska (GoA). However, the processes that transport iron to the ocean surface are poorly quantified. We combine satellite and meteorological data to provide the first description of widespread dust transport from coastal Alaska into the GoA. Dust is frequently transported from glacially-derived sediment at the mouths of several rivers, the most prominent of which is the Copper River. These dust events occur most frequently in autumn, when coastal river levels are low and riverbed sediments are exposed. The dust plumes are transported several hundred kilometers beyond the continental shelf into iron-limited waters. We estimate the mass of dust transported from the Copper River valley during one 2006 dust event to be between 25–80 ktons. Based on conservative estimates, this equates to a soluble iron loading of 30–200 tons. We suggest the soluble Fe flux from dust originating in glaciofluvial sediment deposits from the entire GoA coastline is two to three times larger, and is comparable to the annual Fe flux to GoA surface waters from eddies of coastal origin. Given that glaciers are retreating in the coastal GoA region and in other locations, it is important to examine whether fluxes of dust are increasing from glacierized landscapes to the ocean, and to assess the impact of associated Fe on marine ecosystems.We appreciate support from the USGS CMGP, NCCWSC, the Mendenhall postdoc program, the Woods Hole PEP intern program, and from NASA‐IDS

Wearable sensors for patient-specific boundary shape estimation

It has been shown that accurate boundary form of the forward model is important to minimise artefacts in reconstructed EIT images. This paper presents a proposal for a wearable device based on a network of flexible sensors to evaluate patient-specific boundary form of the forward model for lung EIT. Simulation of approaches using ideal sensors are presented that reconstruct boundaries with low shape error

Study of Mill Island ice core (East Antarctica): A sensitive site for high resolution ocean climate signals?

第2回極域科学シンポジウム　氷床コアセッション 11月16日（水） 国立極地研究所 2階大会議

Position of Aleutian Low Drives Dramatic Inter-Annual Variability in Atmospheric Transport of Glacial Iron to the Gulf of Alaska

Our understanding of glacial flour dust storm delivery of iron to the Gulf of Alaska (GoA) is limited. We interpret concurrent time-series satellite, meteorological, and aerosol geochemical data from the GoA to examine how inter-annual variability in regional weather patterns impacts offshore aerosol glacial iron transport. In 2011, when a northerly Aleutian Low (AL) was persistent during fall, dust emission was suppressed and highly intermittent due to prevalent wet conditions, low winds and a deep early season snowpack. Conversely, in 2012, frequent and prolonged fall dust storms and high offshore glacial iron transport were driven by dry conditions and strong offshore winds generated by persistent strong high pressure over the Alaskan interior and Bering Sea and a southerly AL. Remarkable inter-annual variability in offshore glacial aerosol iron transport indicates that the role of glacial dust in GoA nutrient cycles is likely highly dynamic and particularly sensitive to regional climate forcing

Behavioral deficits in an Angelman syndrome model: Effects of genetic background and age

Angelman syndrome (AS) is a severe neurodevelopmental disorder associated with disruption of maternally inherited UBE3A (ubiquitin protein ligase E3A) expression. At the present time, there is no effective treatment for AS. Mouse lines with loss of maternal Ube3a (Ube3am–/p+) recapitulate multiple aspects of the clinical AS profile, including impaired motor coordination, learning deficits, and seizures. Thus, these genetic mouse models could serve as behavioral screens for preclinical efficacy testing, a critical component of drug discovery for AS intervention. However, the severity and consistency of abnormal phenotypes reported in Ube3am–/p+ mice can vary, dependent upon age and background strain, which is problematic for the detection of beneficial drug effects. As part of an ongoing AS drug discovery initiative, we characterized Ube3am–/p+ mice on either a 129S7/SvEvBrd-Hprtb-m2 (129) or C57BL/6J (B6) background across a range of functional domains and ages to identify reproducible and sufficiently large phenotypes suitable for screening therapeutic compounds. The results from the study showed that Ube3am–/p+ mice have significant deficits in acquisition and reversal learning in the Morris water maze. The findings also demonstrated that Ube3am–/p+ mice exhibit motor impairment in a rotarod task, hypoactivity, reduced rearing and marble-burying, and deficient fear conditioning. Overall, these profiles of abnormal phenotypes can provide behavioral targets for evaluating effects of novel therapeutic strategies relevant to AS

Stem-Loop Recognition by DDX17 Facilitates miRNA Processing and Antiviral Defense

SummaryDEAD-box helicases play essential roles in RNA metabolism across species, but emerging data suggest that they have additional functions in immunity. Through RNAi screening, we identify an evolutionarily conserved and interferon-independent role for the DEAD-box helicase DDX17 in restricting Rift Valley fever virus (RVFV), a mosquito-transmitted virus in the bunyavirus family that causes severe morbidity and mortality in humans and livestock. Loss of Drosophila DDX17 (Rm62) in cells and flies enhanced RVFV infection. Similarly, depletion of DDX17 but not the related helicase DDX5 increased RVFV replication in human cells. Using crosslinking immunoprecipitation high-throughput sequencing (CLIP-seq), we show that DDX17 binds the stem loops of host pri-miRNA to facilitate their processing and also an essential stem loop in bunyaviral RNA to restrict infection. Thus, DDX17 has dual roles in the recognition of stem loops: in the nucleus for endogenous microRNA (miRNA) biogenesis and in the cytoplasm for surveillance against structured non-self-elements

The genomic epidemiology of Escherichia albertii

Escherichia albertii is a recently identified gastrointestinal bacterial pathogen of humans and animals which is typically misidentified and generally only detected during genomic surveillance of other Enterobacteriaceae. The incidence of E. albertii is likely underestimated and its epidemiology and clinical relevance are poorly characterised. Here, we whole genome sequenced E. albertii isolates from humans (n = 83) and birds (n = 79) in Great Britain and analysed a broader public dataset (n = 475) to address these gaps. We found human and avian isolates typically (90%; 148/164) belonged to host-associated monophyletic groups with distinct virulence and antimicrobial resistance profiles. Overlaid patient epidemiological data suggested that human infection was likely related to travel and possibly foodborne transmission. The Shiga toxin encoding stx2f gene was associated with clinical disease (OR = 10.27, 95% CI = 2.98–35.45 p = 0.0002) in finches. Our results suggest that improved future surveillance will further elucidate disease ecology and public and animal health risks associated with E. albertii