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Influenza A Virus Host Shutoff Disables Antiviral Stress-Induced Translation Arrest
Influenza A virus (IAV) polymerase complexes function in the nucleus of infected cells, generating mRNAs that bear 5′ caps and poly(A) tails, and which are exported to the cytoplasm and translated by host machinery. Host antiviral defences include mechanisms that detect the stress of virus infection and arrest cap-dependent mRNA translation, which normally results in the formation of cytoplasmic aggregates of translationally stalled mRNA-protein complexes known as stress granules (SGs). It remains unclear how IAV ensures preferential translation of viral gene products while evading stress-induced translation arrest. Here, we demonstrate that at early stages of infection both viral and host mRNAs are sensitive to drug-induced translation arrest and SG formation. By contrast, at later stages of infection, IAV becomes partially resistant to stress-induced translation arrest, thereby maintaining ongoing translation of viral gene products. To this end, the virus deploys multiple proteins that block stress-induced SG formation: 1) non-structural protein 1 (NS1) inactivates the antiviral double-stranded RNA (dsRNA)-activated kinase PKR, thereby preventing eIF2α phosphorylation and SG formation; 2) nucleoprotein (NP) inhibits SG formation without affecting eIF2α phosphorylation; 3) host-shutoff protein polymerase-acidic protein-X (PA-X) strongly inhibits SG formation concomitant with dramatic depletion of cytoplasmic poly(A) RNA and nuclear accumulation of poly(A)-binding protein. Recombinant viruses with disrupted PA-X host shutoff function fail to effectively inhibit stress-induced SG formation. The existence of three distinct mechanisms of IAV-mediated SG blockade reveals the magnitude of the threat of stress-induced translation arrest during viral replication
Capital account regulations and the trading system: a compatibility review
This repository item contains a single issue of the Pardee Center Task Force Reports, a publication series that began publishing in 2009 by the Boston University Frederick S. Pardee Center for the Study of the Longer-Range Future. Spanish version produced by the Center for the Study of State and Society, Buenos Aires.
Portuguese version coordinated by Daniela Magalhaes Prates, a contributing author of the report, in collaboration with Ana Trivellato (translator), and Maria Inês Amorozo (graphic designer).This report is the product of the Pardee Center Task Force on Regulating Capital Flows for Long-Run Development and builds on the Task Force´s first report published in March 2012.
The Pardee Center Task Force was convened initially in September 2011 as consensus was emerging that the global financial crisis has re-confirmed the need to regulate cross-border finance. The March 2012 report argues that international financial institutions – and in particular the International Monetary Fund – need to support measures that would allow capital account regulations (CARs) to become a standard and effective part of the macroeconomic policy toolkit. Yet some policymakers and academics expressed concern that many nations — and especially developing countries — may not have the flexibility to adequately deploy such regulations because of trade and investment treaties they are party to.
In June 2012, the Pardee Center, with the Center for the Study of State and Society (CEDES) in Argentina and Global Development and Environment Institute (GDAE) at Tufts University, convened a second Task Force workshop in Buenos Aires specifically to review agreements at the WTO and various Free Trade Agreements (FTAs) and Bilateral Investment Treaties (BITs) for the extent to which the trading regime is compatible with the ability to deploy effective capital account regulations. This report presents the findings of that review, and highlights a number of potential incompatibilities found between the trade and investment treaties and the ability to deploy CARs. It also highlights an alarming lack of policy space to use CARs under a variety of FTAs and BITs—especially those involving the United States. Like the first report, it was written by an international group of experts whose goal is to help inform discussions and decisions by policymakers at the IMF and elsewhere that will have implications for the economic health and development trajectories for countries around the world
Objective metric of energy absorbed in tibial plateau fractures corresponds well to clinician assessment of fracture severity
Objectives
Determine the agreement between subjective assessments of fracture severity and an objective CT-based metric of fracture energy in tibial plateau fractures.
Methods
Six fellowship-trained orthopaedic trauma surgeons independently rank-ordered 20 tibial plateau fractures in terms of severity based upon AP and lateral knee radiographs. A CT-based image analysis methodology was used to quantify the fracture energy, and agreement between the surgeons’ severity rankings and the fracture energy metric was tested by computing their concordance, a statistical measure that estimates the probability that any two cases would be ranked with the same ordering by two different raters or methods.
Results
Concordance between the six orthopaedic surgeons ranged from 82% to 93%, and concordance between surgeon severity rankings and the computed fracture energy ranged from 73% to 78%.
Conclusions
There is a high level of agreement between experienced surgeons in their assessments of tibial plateau fracture severity, and a slightly lower agreement between the surgeon assessments and an objective CT-based metric of fracture energy. Taken together, these results suggest that experienced surgeons share a similar understanding of what makes a tibial plateau fracture more or less severe, and an objective CT-based metric of fracture energy captures much but not all of that information. Further research is ongoing to characterize the relationship between surgeon assessments of severity, fracture energy, and the eventual clinical outcomes for patients with fractures of the tibial plateau
WASP-44b, WASP-45b and WASP-46b: three short-period, transiting extrasolar planets
We report the discovery of three extrasolar planets that transit their
moderately bright (Vmag = 12-13) host stars. WASP-44b is a 0.89-MJup planet in
a 2.42-day orbit around a G8V star. WASP-45b is a 1.03-MJup planet which passes
in front of the limb of its K2V host star every 3.13 days. Weak Ca II H+K
emission seen in the spectra of WASP-45 suggests the star is chromospherically
active. WASP-46b is a 2.10-MJup planet in a 1.43-day orbit around a G6V star.
Rotational modulation of the light curves of WASP-46 and weak Ca II H+K
emission in its spectra show the star to be photospherically and
chromospherically active.
We imposed circular orbits in our analyses as the radial velocity data are
consistent with (near-)circular orbits, as could be expected from both
empirical and tidal-theory perspectives for such short-period, Jupiter-mass
planets. We discuss the impact of fitting for eccentric orbits for such planets
when not supported by the data. The derived planetary and stellar radii depend
on the fitted eccentricity and these parameters inform intense theoretical
efforts concerning tidal circularisation and heating, bulk planetary
composition and the observed systematic errors in planetary and stellar radii.
As such, we recommend exercising caution in fitting the orbits of short period,
Jupiter-mass planets with an eccentric model when there is no evidence of
non-circularity.Comment: 12 pages, 8 figures, 6 tables. As accepted for publication in MNRA
WASP-30b: a 61 Mjup brown dwarf transiting a V=12, F8 star
We report the discovery of a 61-Jupiter-mass brown dwarf, which transits its
F8V host star, WASP-30, every 4.16 days. From a range of age indicators we
estimate the system age to be 1-2 Gyr. We derive a radius (0.89 +/- 0.02 RJup)
for the companion that is consistent with that predicted (0.914 RJup) by a
model of a 1-Gyr-old, non-irradiated brown dwarf with a dusty atmosphere. The
location of WASP-30b in the minimum of the mass-radius relation is consistent
with the quantitative prediction of Chabrier & Baraffe (2000), thus confirming
the theory.Comment: As accepted for publication in ApJL (6 pages, 2 figures, 3 tables
The first WASP public data release
The WASP (wide angle search for planets) project is an exoplanet transit survey that has been automatically taking wide field images since 2004. Two instruments, one in La Palma and the other in South Africa, continually monitor the night sky, building up light curves of millions of unique objects. These light curves are used to search for the characteristics of exoplanetary transits. This first public data release (DR1) of the WASP archive makes available all the light curve data and images from 2004 up to 2008 in both the Northern and Southern hemispheres. A web interface () to the data allows easy access over the Internet. The data set contains 3 631 972 raw images and 17 970 937 light curves. In total the light curves have 119 930 299 362 data points available between them
WASP-44b, WASP-45b and WASP-46b: three short-period, transiting extrasolar planets
We report the discovery of three extrasolar planets that transit their moderately bright (mV= 12-13) host stars. WASP-44b is a 0.89-MJup planet in a 2.42-day orbit around a G8V star. WASP-45b is a 1.03-MJup planet which passes in front of the limb of its K2V host star every 3.13 days. Weak Ca ii H&K emission seen in the spectra of WASP-45 suggests that the star is chromospherically active. WASP-46b is a 2.10-MJup planet in a 1.43-day orbit around a G6V star. Rotational modulation of the light curves of WASP-46 and weak Ca ii H&K emission in its spectra show the star to be photospherically and chromospherically active. We imposed circular orbits in our analyses as the radial-velocity data are consistent with (near-)circular orbits, as could be expected from both empirical and tidal-theory perspectives for such short-period, ∼Jupiter-mass planets. We discuss the impact of fitting for eccentric orbits for such planets when not supported by the data. The derived planetary and stellar radii depend on the fitted eccentricity and these parameters inform intense theoretical efforts concerning tidal circularization and heating, bulk planetary composition and the observed systematic errors in planetary and stellar radii. As such, we recommend exercising caution in fitting the orbits of short-period, ∼Jupiter-mass planets with an eccentric model when there is no evidence of non-circularit
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Passive sampling methods for contaminated sediments: Risk assessment and management
This paper details how activity-based passive sampling methods (PSMs), which provide information on bioavailability in terms of freely dissolved contaminant concentrations (Cfree), can be used to better inform risk management decision making at multiple points in the process of assessing and managing contaminated sediment sites. PSMs can increase certainty in site investigation and management, because Cfree is a better predictor of bioavailability than total bulk sediment concentration (Ctotal) for 4 key endpoints included in conceptual site models (benthic organism toxicity, bioaccumulation, sediment flux, and water column exposures). The use of passive sampling devices (PSDs) presents challenges with respect to representative sampling for estimating average concentrations and other metrics relevant for exposure and risk assessment. These challenges can be addressed by designing studies that account for sources of variation associated with PSMs and considering appropriate spatial scales to meet study objectives. Possible applications of PSMs include: quantifying spatial and temporal trends in bioavailable contaminants, identifying and evaluating contaminant source contributions, calibrating site-specific models, and, improving weight-of-evidence based decision frameworks. PSM data can be used to assist in delineating sediment management zones based on likelihood of exposure effects, monitor remedy effectiveness, and, evaluate risk reduction after sediment treatment, disposal, or beneficial reuse after management actions. Examples are provided illustrating why PSMs and freely dissolved contaminant concentrations (Cfree) should be incorporated into contaminated sediment investigations and study designs to better focus on and understand contaminant bioavailability, more accurately estimate exposure to sediment-associated contaminants, and better inform risk management decisions. Research and communication needs for encouraging broader use are discussed. Integr Environ Assess Manag 2014;10:224–236. © 2014 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of SETAC
The 0.5MJ transiting exoplanet WASP-13b
We report the discovery of WASP-13b, a low-mass M_{\rm p} = 0.46 ^_~M_J transiting exoplanet with an orbital period of 4.35298 0.00004 days. The transit has a depth of 9 mmag, and although our follow-up photometry does not allow us to constrain the impact parameter well (0 < b < 0.46), with radius in the range ~ 1.06-1.21 RJ the location of WASP-13b in the mass-radius plane is nevertheless consistent with H/He-dominated, irradiated, low core mass and core-free theoretical models. The G1V host star is similar to the Sun in mass (M__ ~M_{\odot}) and metallicity ([M/H] = 0.00.2), but is possibly older ( 8.5^_{\rm -4.9} Gyr)
Tracking neonicotinoids following their use as cotton seed treatments
Neonicotinoids are a leading class of insecticides on the global market, accounting for nearly 25%. They are widely used in both agricultural and residential settings. Causing neuron failure by irreversibly binding to the insect nicotinic acetylcholine receptor, neonicotinoids offer broad spectrum efficacy against a variety of pests. However, because they are non-selective with regard to insect species, there has been some concern with neonicotinoid use over threats to pollinators such as honeybees, and potential indirect effects to migratory waterfowl as a result of invertebrate prey population depletion. In order to study occurrence and fate of neonicotinoids (thiamethoxam and imidacloprid), we analyzed cotton leaves on plants grown from neonicotinoid-treated seeds and corresponding soil samples between cotton rows. Neonicotinoid concentration data from cotton leaves appears to be consistent with the claim that seed treatments protect plants for 3–4 weeks; by 30 days post-planting, neonicotinoid concentrations fell, in general, to 200 ng/g or lower. This represents about a 10-fold decrease from plant concentrations at approximately 2 weeks post-planting. It was found that neonicotinoids used as seed treatments remained present in the soil for months post planting and could be available for runoff. To that end, 21 playa wetlands were sampled; 10 had at least one quantifiable neonicotinoid present, three of which were classified as grassland or rangeland playas, two were urban, and the remaining five were cropland playas. In several instances, neonicotinoid concentrations in playas exceeded EPA chronic benchmarks for aquatic invertebrates
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