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CRISPR strategy to cure latent herpes infection [Medical Sciences]

PNAS Early Edition Articles - Mon, 08/25/2014 - 13:38
Latent viral infection is a persistent cause of human disease. Although standard antiviral therapies can suppress active viral replication, no existing treatment can effectively eradicate latent infection and therefore a cure is lacking for many prevalent viral diseases. The prokaryotic immune system clustered regularly interspaced short palindromic repeat (CRISPR)/Cas evolved...

RSV attenuation by codon-pair deoptimization [Microbiology]

PNAS Early Edition Articles - Mon, 08/25/2014 - 13:38
Human respiratory syncytial virus (RSV) is the most important viral agent of serious pediatric respiratory-tract disease worldwide. A vaccine or generally effective antiviral drug is not yet available. We designed new live attenuated RSV vaccine candidates by codon-pair deoptimization (CPD). Specifically, viral ORFs were recoded by rearranging existing synonymous codons...

Free energy time course of EMT [Chemistry]

PNAS Early Edition Articles - Mon, 08/25/2014 - 13:38
The epithelial-to-mesenchymal transition (EMT) initiates the invasive and metastatic behavior of many epithelial cancers. Mechanisms underlying EMT are not fully known. Surprisal analysis of mRNA time course data from lung and pancreatic cancer cells stimulated to undergo TGF-β1–induced EMT identifies two phenotypes. Examination of the time course for these phenotypes...

Climatologist Dr. Judith Curry rips UN IPCC’s ‘expert judgement’ that humans are ‘extremely likely’ responsible for more than half of warming since 1951

Climate Depot - Sun, 08/24/2014 - 16:29
The IPCC does not have a convincing explanation for: warming from 1910-1940 cooling from 1940-1975 hiatus from 1998 to present The IPCC purports to have a highly confident explanation for the warming since 1950, but it was only during the period 1976-2000 when the global surface temperatures actually increased. The absence of convincing attribution of [...]

Seafloor methane: Atlantic bubble bath

Nature Geoscience Advanced Online - Sat, 08/23/2014 - 23:00

Nature Geoscience. doi:10.1038/ngeo2238

Author: John Kessler

The release of large quantities of methane from ocean sediments might affect global climate change. The discovery of expansive methane seeps along the US Atlantic margin provides an ideal test bed for such a marine methane–climate connection.

Optimum vegetation height and density for inorganic sedimentation in deltaic marshes

Nature Geoscience Advanced Online - Sat, 08/23/2014 - 23:00

Nature Geoscience. doi:10.1038/ngeo2233

Authors: William Nardin & Douglas A. Edmonds

River deltas support a disproportionate percentage of the world’s population and some are drowning as sea level rises. Resilient deltas theoretically balance relative sea-level rise with vertical growth from surface sedimentation. Vegetation generally enhances inorganic sedimentation and resiliency in some settings, such as tidal saltwater marshes, but the effect of vegetation on freshwater marshes in river deltas is less clear. Here we use a hydrodynamic numerical model to simulate deposition in a river delta with varying vegetation characteristics and water discharge and show that vegetation does not always enhance sedimentation on a freshwater marsh. For a given flood, we find that intermediate vegetation height and density are optimal for enhancing both sand and mud deposition, whereas tall or dense vegetation causes sand to remain in the river channel, reducing marsh sedimentation. A multivariate regression analysis of remote-sensing data from Wax Lake Delta, Louisiana, USA shows that the delta exhibits a hydrodynamic response to vegetation in agreement with model predictions. Because most sediment is delivered to freshwater deltaic marshes by infrequent storm and flood events, we further suggest that the timing of such events relative to seasonal vegetation growth determines the integrated effect of vegetation on delta resiliency.

Record of the ancient martian hydrosphere and atmosphere preserved in zircon from a martian meteorite

Nature Geoscience Advanced Online - Sat, 08/23/2014 - 23:00

Nature Geoscience. doi:10.1038/ngeo2231

Authors: A. A. Nemchin, M. Humayun, M. J. Whitehouse, R. H. Hewins, J-P. Lorand, A. Kennedy, M. Grange, B. Zanda, C. Fieni & D. Deldicque

Mars exhibits ample evidence for an ancient surface hydrosphere. The oxygen isotope compositions of carbonate minerals and alteration products in martian meteorites suggest that this ancient hydrosphere was not in isotopic equilibrium with the martian lithosphere. Martian meteorite NWA 7533 is composed of regolith breccia from the heavily cratered terrains of ancient Mars and contains zircon grains for which U–Pb ages have been reported. Here we report variations between the oxygen isotopic compositions of four zircon grains from NWA 7533. We propose that these variations can be explained if the mantle melts from which the zircon crystallized approximately 4.43 Gyr ago had assimiliated 17O-enriched regolith materials, and that some of the zircon grains, while in a metamict state, were later altered by low-temperature fluids near the surface less than 1.7 Gyr ago. Enrichment of the martian regolith in 17O before the zircon crystallized, presumably through exchange with the 17O-enriched atmosphere or hydrosphere during surface alteration, suggests that the thick primary atmosphere of Mars was lost within the first 120 Myr after accretion. We conclude that the observed variation of 17O anomalies in zircon from NWA 7533 points to prolonged interaction between the martian regolith, atmosphere and hydrosphere.

Resilience of Pacific pelagic fish across the Cretaceous/Palaeogene mass extinction

Nature Geoscience Advanced Online - Sat, 08/23/2014 - 23:00

Nature Geoscience. doi:10.1038/ngeo2227

Authors: Elizabeth C. Sibert, Pincelli M. Hull & Richard D. Norris

Open-ocean ecosystems experienced profound disruptions to biodiversity and ecological structure during the Cretaceous/Palaeogene mass extinction about 66 million years ago. It has been suggested that during this mass extinction, a collapse of phytoplankton production rippled up the food chain, causing the wholesale loss of consumers and top predators. Pelagic fish represent a key trophic link between primary producers and top predators, and changes in their abundance provide a means to examine trophic relationships during extinctions. Here we analyse accumulation rates of microscopic fish teeth and shark dermal scales (ichthyoliths) in sediments from the Pacific Ocean and Tethys Sea across the Cretaceous/Palaeogene extinction to reconstruct fish abundance. We find geographic differences in post-disaster ecosystems. In the Tethys Sea, fish abundance fell abruptly at the Cretaceous/Palaeogene boundary and remained depressed for at least 3 million years. In contrast, fish abundance in the Pacific Ocean remained at or above pre-boundary levels for at least four million years following the mass extinction, despite marked extinctions in primary producers and other zooplankton consumers in this region. We suggest that the mass extinction did not produce a uniformly dead ocean or microbially dominated system. Instead, primary production, at least regionally, supported ecosystems with mid-trophic-level abundances similar to or above those of the Late Cretaceous.

Widespread methane leakage from the sea floor on the northern US Atlantic margin

Nature Geoscience Advanced Online - Sat, 08/23/2014 - 23:00

Nature Geoscience. doi:10.1038/ngeo2232

Authors: A. Skarke, C. Ruppel, M. Kodis, D. Brothers & E. Lobecker

Methane emissions from the sea floor affect methane inputs into the atmosphere, ocean acidification and de-oxygenation, the distribution of chemosynthetic communities and energy resources. Global methane flux from seabed cold seeps has only been estimated for continental shelves, at 8 to 65 Tg CH4 yr−1, yet other parts of marine continental margins are also emitting methane. The US Atlantic margin has not been considered an area of widespread seepage, with only three methane seeps recognized seaward of the shelf break. However, massive upper-slope seepage related to gas hydrate degradation has been predicted for the southern part of this margin, even though this process has previously only been recognized in the Arctic. Here we use multibeam water-column backscatter data that cover 94,000 km2 of sea floor to identify about 570 gas plumes at water depths between 50 and 1,700 m between Cape Hatteras and Georges Bank on the northern US Atlantic passive margin. About 440 seeps originate at water depths that bracket the updip limit for methane hydrate stability. Contemporary upper-slope seepage there may be triggered by ongoing warming of intermediate waters, but authigenic carbonates observed imply that emissions have continued for more than 1,000 years at some seeps. Extrapolating the upper-slope seep density on this margin to the global passive margin system, we suggest that tens of thousands of seeps could be discoverable.

Psychiatrist likens global warming ‘devastation’ to Hiroshima/Nagasaki blasts in NYTimes op-ed

Climate Depot - Sat, 08/23/2014 - 17:58
Psychiatrist likens global warming ‘devastation’ to Hiroshima/Nagasaki blasts in NYTimes op-ed. http://goo.gl/tJPnu6 #GetTheButterflyNet https://twitter.com/JunkScience/status/503259901658148865

U.S. Summer Chill: NOAA – 1025 Cold Records Broken From Aug 1 to Aug 21. Some records Smashed by 16F

Climate Depot - Sat, 08/23/2014 - 14:25
Via:  http://sunshinehours.wordpress.com/2014/08/23/noaa-1025-low-max-records-broken-from-aug-1-to-aug-21-some-by-16f/ 1025 Low Max Records Broken From Aug 1 to Aug 21 according to the NOAA. A “Low Max” means that the maximum temperatures for the day was the lowest it has ever been. This indicates daytime cooling. Below is a screenshot showing location and the biggest difference between old record and new record. Note that Dyer NV [...]

Cold summer: US daily record minimums outnumbering record maximums 3 to 1 in the last 30 days

Climate Depot - Sat, 08/23/2014 - 14:04
Cold summer: US daily record minimums outnumbering record maximums 3 to 1 in the last 30 days http://wattsupwiththat.com/2014/08/23/cold-summer-us-daily-record-minimum-outnumbering-record-maximums-3-to-1-in-the-last-30-days Plus, there have been new snowfall records, almost unheard of in summer. See the table: Source: http://www.ncdc.noaa.gov/cdo-web/datatools/records Daily records  Tmax=368  Tmin =1072 Monthly records Tmax=6 Tmin= 17 3 new snow records. I had noted earlier this year [...]

NOAA – 1025 Low Max Records Broken From Aug 1 to Aug 21. Some by 16F

Climate Depot - Sat, 08/23/2014 - 14:02
NOAA – 1025 Low Max Records Broken From Aug 1 to Aug 21. Some by 16F http://sunshinehours.wordpress.com/2014/08/23/noaa-1025-low-max-records-broken-from-aug-1-to-aug-21-some-by-16f 1025 Low Max Records Broken From Aug 1 to Aug 21 according to the NOAA. A “Low Max” means that the maximum temperatures for the day was the lowest it has ever been. This indicates daytime cooling. Below is [...]

Record Lows Outnumber Highs 3:1 – But You Won’t Hear It From PBS!

Climate Depot - Sat, 08/23/2014 - 13:56
Record Lows Outnumber Highs 3:1 – But You Won’t Hear It From PBS! http://notalotofpeopleknowthat.wordpress.com/2014/08/23/record-lows-outnumber-highs-31-but-you-wont-hear-it-from-pbs By Paul Homewood    http://notalotofpeopleknowthat.wordpress.com/2013/11/15/pbs-still-pedalling-the-record-temperature-con/   It was not long ago that we were bombarded with claims of record high temperatures in the US. For instance, PBS introduced their new widget in 2011, shown above, to track daily records. As they [...]

Dramatic Antarctic Freeze Up…Iciest Decade Ever On Satellite Record…Every Decade Icier Than The Previous!

Climate Depot - Sat, 08/23/2014 - 13:49
Dramatic Antarctic Freeze Up…Iciest Decade Ever On Satellite Record…Every Decade Icier Than The Previous! http://notrickszone.com/2014/08/23/dramatic-antarctic-freeze-up-iciest-decade-ever-on-record-every-decade-icier-than-the-previous/ Nowhere have records been falling faster than in Antarctica. And what is shocking is that these records are all tied to cooling – and not warming. Antarctica has been setting new maximum sea ice records almost daily, and never has [...]
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