Pancreatic cancer patient survival correlates with DNA methylation of pancreas development genes.

DNA methylation is an epigenetic mark associated with regulation of transcription and genome structure. These markers have been investigated in a variety of cancer settings for their utility in differentiating normal tissue from tumor tissue. Here, we examine the direct correlation between DNA methylation and patient survival. We find that changes in the DNA methylation of key pancreatic developmental genes are strongly associated with patient survival

The Seasonal Cycle and Interannual Variability in Stratospheric Temperatures and Links to the Brewer–Dobson Circulation: An Analysis of MSU and SSU Data

Previous studies have shown that lower-stratosphere temperatures display a near-perfect cancellation between tropical and extratropical latitudes on both annual and interannual time scales. The out-of-phase relationship between tropical and high-latitude lower-stratospheric temperatures is a consequence of variability in the strength of the Brewer–Dobson circulation (BDC). In this study, the signal of the BDC in stratospheric temperature variability is examined throughout the depth of the stratosphere using data from the Stratospheric Sounding Unit (SSU). While the BDC has a seemingly modest signal in the annual cycle in zonal-mean temperatures in the mid- and upper stratosphere, it has a pronounced signal in the month-to-month and interannual variability. Tropical and extratropical temperatures are significantly negatively correlated in all SSU channels on interannual time scales, suggesting that variations in wave driving are a major factor controlling global-scale temperature variability not only in the lower stratosphere (as shown in previous studies), but also in the mid- and upper stratosphere. The out-of-phase relationship between tropical and high latitudes peaks at all levels during the cold-season months: December–March in the Northern Hemisphere and July–October in the Southern Hemisphere. In the upper stratosphere, the out-of-phase relationship with high-latitude temperatures extends beyond the tropics and well into the extratropics of the opposite hemisphere. The seasonal cycle in stratospheric temperatures follows the annual march of insolation at all levels and latitudes except in the mid- to upper tropical stratosphere, where it is dominated by the semiannual oscillation. M

On the Signatures of Equatorial and Extratropical Wave Forcing in Tropical Tropopause Layer Temperatures

Temperatures in the tropical tropopause layer (TTL) play an important role in stratosphere–troposphere exchange and in the formation and maintenance of thin cirrus clouds. Many previous studies have examined the contributions of extratropical and equatorial waves to the TTL using coarse-vertical-resolution satellite and reanalysis data. In this study, the authors provide new insight into the role of extratropical and equatorial waves in the TTL using high-vertical-resolution GPS radio occultation data. The results examine the influence of four different wave forcings on the TTL: extratropical waves that propagate vertically into the stratosphere, extratropical waves that propagate meridionally into the subtropical stratosphere, extratropical waves that propagate meridionally into the subtropical troposphere, and the equatorial planetary waves. The vertically and meridionally propagating extratropical stratospheric waves are associated with deep, zonally symmetric temperature anomalies that extend and amplify with height throughout the lower-to-middle tropical stratosphere. In contrast, the extratropical tropospheric waves and the equatorial planetary waves are associated with tropical temperature anomalies that are confined below 20-km altitude. The equatorial planetary waves dominate the zonally asymmetric component of the TTL temperature field, and both the equatorial planetary waves and the extratropical tropospheric waves are linked to large temperature variability in a 1–2-km-deep layer near the tropical tropopause. The fine vertical scale of the TTL temperature features associated with the equatorial planetary waves and the extratropical tropospheric waves is only readily apparent in high-vertical-resolution data

The Pacific Center of Action of the Northern Hemisphere Annular Mode: Real or Artifact?

The leading empirical orthogonal function (EOF) of the sea level pressure (SLP) field, referred to as the Arctic Oscillation (AO) or Northern Hemisphere annular mode (NAM), consists of a dipole between the polar cap region and the surrounding zonal ring centered along 458N. Embedded within the outer ring are centers of action over the Euro-Atlantic and Pacific sectors in which SLP fluctuates in phase. That the observed SLP fluctuations at these two centers of action are virtually uncorrelated raises the question of whether the Pacific center in the annular mode could be an artifact of EOF analysis. It is argued that sea level pressure fluctuations at the Pacific and Euro-Atlantic centers of action of the AO/ NAM would be more strongly correlated were it not for the fact that SLP variability over the North Pacific is dominated by a pattern in which fluctuations over the North Atlantic and North Pacific are inversely related. Evidence of the coexistence of such a pattern, which resembles an augmented version of the Pacific–North American pattern, is presented

Observed connections of Arctic stratospheric ozone extremes to Northern Hemisphere surface climate

We present observational evidence for linkages between extreme Arctic stratospheric ozone anomalies in March and Northern Hemisphere tropospheric climate in spring (March–April). Springs characterized by low Arctic ozone anomalies in March are associated with a stronger, colder polar vortex and circulation anomalies consistent with the positive polarity of the Northern Annular Mode/North Atlantic Oscillation in March and April. The associated spring tropospheric circulation anomalies indicate a poleward shift of zonal winds at 500 hPa over the North Atlantic. Furthermore, correlations between March Arctic ozone and March–April surface temperatures reveal certain regions where a surprisingly large fraction of the interannual variability in spring surface temperatures is associated with interannual variability in ozone. We also find that years with low March Arctic ozone in the stratosphere display surface maximum daily temperatures in March–April that are colder than normal over southeastern Europe and southern Asia, but warmer than normal over northern Asia, adding to the warming from increasing well-mixed greenhouse gases in those locations. The results shown here do not establish causality, but nevertheless suggest that March stratospheric ozone is a useful indicator of spring averaged (March–April) tropospheric climate in certain Northern Hemispheric regions.National Science Foundation (U.S.) (AGS-1539972

N-Terminal Phosphorylation Sites of Herpes Simplex Virus 1 ICP0 Differentially Regulate Its Activities and Enhance Viral Replication

This is the publisher's version, also available electronically from http://jvi.asm.org/content/87/4/2109The herpes simplex virus 1 (HSV-1) infected cell protein 0 (ICP0) is an immediate-early phosphoprotein that transactivates viral gene expression. Evidence suggests that phosphorylation regulates the functions of ICP0, and three regions (termed regions I, II, and III) in the protein are known to be phosphorylated. Mutation of the putative phosphorylation sites within region I, termed Phos 1, which lies in the N-terminal portion of ICP0, impairs the E3 ubiquitin (Ub) ligase and ND10-disrupting activities of ICP0 in cell culture and diminishes viral replication. To identify the specific phosphorylation site(s) or residues responsible for the phenotypes observed with Phos 1, individual residues within region I were mutated to alanine (S224A, T226A, T231A, and T232A) and one double mutant S224A/T226A was constructed. Tissue culture studies demonstrated that the S224A, S224A/T226A, T231A, and T232A mutants were unable to dissociate the cellular protein PML from ND10 and that the S224/T226A mutant was defective in its ability to dissociate the cellular protein Sp100 from ND10. Additionally, the transactivation activity of ICP0 was impaired in the S224A and S224A/T226A mutants. The S224A and S224A/T226A mutant forms were more stable than wild-type ICP0, suggesting that their ability to autoubiquitinate was limited. Moreover, one ICP0 ubiquitination target, USP-7, was also more stable after infection with these two mutants. Lastly, the replication of the S224A and S224A/T226A mutant viruses was reduced in cell culture and in vivo. Overall, our data suggest that specific phosphorylation sites within region I differentially regulate the activities of ICP0, which are required for efficient viral replication

Exploring the Extreme Universe with the Fermi Gamma-Ray Space Telescope

In ways similar to experiments in nuclear and particle physics, high-energy astrophysics usesgamma rays and energetic charged particles toprobe processes that involve large energy transfers.Since its launch in 2008, the international Fermi Gamma-Ray Space Telescope has been exploringnatural particle accelerators and the interactionsof high-energy particles in the universe. Withsources ranging from thunderstorms on Earth to galaxies and exploding stars in distant parts of the cosmos, the telescopes subjects of study are almostas diverse as were those of the scientist whose name it bears

Quantifying the Lead Time Required for a Linear Trend to Emerge from Natural Climate Variability

This study introduces a simple analytic expression for calculating the lead time required for a linear trend to emerge in a Gaussian first-order autoregressive process. The expression is derived from the standard error of the regression and is tested using the NCAR Community Earth System Model Large Ensemble of climate change simulations. It is shown to provide a robust estimate of the point in time when the forced signal of climate change has emerged from the natural variability of the climate system with a predetermined level of statistical confidence. The expression provides a novel analytic tool for estimating the time of emergence of anthropogenic climate change and its associated regional climate impacts from either observed or modeled estimates of natural variability and trends.National Science Foundation (U.S.). Climate and Large-Scale Dynamics Program (Grant AGS-1419667

A New Perspective on Coastally Trapped Disturbances Using Data from the Satellite Era

The ability of global climate models to simulate accurately marine stratiform clouds continues to challenge the atmospheric science community. These cloud types, which account for a large uncertainty in Earth’s radiation budget, are generally difficult to characterize due to their shallowness and spatial inhomogeneity. Previous work investigating marine boundary layer (MBL) clouds off the California coast has focused on clouds that form under the typical northerly flow regime during the boreal warm season. From about June through September, however, these northerly winds may reverse and become southerly as part of a coastally trapped disturbance (CTD). As the flow surges northward, it is accompanied by a broad cloud deck. Because these events are difficult to forecast, in situ observations of CTDs are few and far between, and little is known about their cloud physical properties. A climatological perspective of 23 CTD events—spanning the years from 2004 to 2016—is presented using several data products, including model reanalyses, buoys, and satellites. For the first time, satellite retrievals suggest that CTD cloud decks may play a unique role in the radiation budget due to a combination of aerosol sources that enhance cloud droplet number concentration and reduce cloud droplet effective radius. This particular type of cloud regime should therefore be treated differently than that which is more commonly found in the summertime months over the northeast Pacific Ocean. The potential influence of a coherent wind stress cycle on sea surface temperatures and sea salt aerosol is also explored

Delivering services by building and running virtual organisations

Non peer reviewedPostprin