Article on bacterial communities of the coronal sulcus and distal urethra of adolescent males.

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A screening study of the steam reforming reaction on clean and oxygen covered early transition-metal carbides surfaces is performed by means of density-functional theory calculations. It is found that carbides provide a wide spectrum of reactivities, from too reactive via suitable to too inert. Several molybdenum-based systems are identified as possible steam reforming catalysts. The findings suggest that carbides provide a playground for reactivity tuning, comparable to the one for pure metals.

The RAGS (Radiochemical Analysis of Gaseous Samples) diagnostic apparatus was recently installed at the National Ignition Facility. Following a NIF shot, RAGS is used to pump the gas load from the NIF chamber for purification and isolation of the noble gases. After collection, the activated gaseous species are counted via gamma spectroscopy for measurement of the capsule areal density and fuel-ablator mix. Collection efficiency was determined by injecting a known amount of {sup 135}Xe into the NIF chamber, which was then collected with RAGS. Commissioning was performed with an exploding pusher capsule filled with isotopically enriched {sup 124}Xe and {sup 126}Xe added to the DT gas fill. Activated xenon species were recovered post-shot and counted via gamma spectroscopy. Results from the collection and commissioning tests are presented. The performance of RAGS allows us to establish a noble gas collection method for measurement of noble gas species produced via neutron and charged particle reactions in a NIF capsule.

In 2008, the Particle Physics Project Prioritization Panel identified three frontiers for research in high energy physics, the Energy Frontier, the Intensity Frontier, and the Cosmic Frontier. In this paper, I will describe how Fermilab is configuring and upgrading the accelerator complex, prior to the development of Project X, in support of the Intensity Frontier.

NASA's JUNO mission will arrive at Jupiter in July 2016, after nearly five years in space. Since operational costs tend to rise with mission time, minimizing such times becomes a top priority. We present the conceptual design for a 10MW aneutronic fusion engine with high exhaust velocities that would reduce transit time for a Jupiter mission to eighteen months and enable more challenging exploration missions in the solar system and beyond. __________________________________________________

Numerous electron beam applications would benefit from increased average current without sacrificing beam brightness. Work is underway at LLNL to investigate the performance of X-band photoinjectors that would generate electron bunches at a rate matching the RF drive frequency, i.e. one bunch per RF cycle. A critical part of this effort involves development of photo-cathode drive laser technology. Here we present a new laser architecture that can generate pulse trains at repetition rates up to several GHz. This compact, fiber-based system is driven directly by the accelerator RF and so is inherently synchronized with the accelerating fields, and scales readily over a wide range of drive frequencies (L-band through X-band). The system will be required to produce 0.5 {mu}J, {approx}200 fs rise time, spatially and temporally shaped UV pulses designed to optimize the electron beam brightness. Presented is the current status of this system, producing 2 ps pulses from a continuous-wave source.

The presence of significant intensities of un-bunched beam is a potentially serious issue in the LHC. Procedures using damper kickers for cleaning both the Abort Gap (AG) and the buckets targeted for injection, are currently in operation at flat bottom. Recent observations of relatively high population of the AG during physics runs brought up the need for AG cleaning during luminosity operation. In this paper the results of experimental studies performed in October 2011 are presented.

A muon-to-electron conversion experiment at Fermilab, Mu2e, is being designed to probe for new physics beyond the standard model at mass scales up to 10{sup 4} TeV. For this experiment, the advance in experimental sensitivity will be four orders of magnitude when compared to existing data on charged lepton flavor violation. The muon beam will be produced by delivering a proton beam contained in short 100-ns bunches onto a muon production target, with an inter-bunch separation of about 1700 ns. A critical requirement of the experiment is to ensure a low level of background at the muon detector consistent with the required sensitivity. To meet the sensitivity requirement, protons that reach the target between bunches must be suppressed by an enormous factor, so that an extinction factor, defined as a number of background protons between main bunches per proton in such a bunch, should not exceed 10{sup -9}. This paper describes the advanced beam optics and results of numerical modeling with STRUCT and MARS codes for a beam line with a collimation system that allows us to achieve the experimental extinction factor of one per billion.