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As part of the mission to cure and ultimately eliminate tuberculosis (TB), maintaining treatment adherence poses a substantial barrier (1). Persons with TB must complete multidrug regimens typically lasting [greater [...]

Gas-flow proportional counting systems are used by the Radiation Metrology Laboratory (RML) at Sandia National Laboratories for reactor fluence monitoring with the 32S(n,p)32P reaction. Calibration of these systems has traditionally been accomplished by fluence-transfer irradiations at the NIST 252Cf facility. Such calibrations have become increasingly difficult as the NIST 252Cf source decayed to unusable levels. To minimize the risk to the testing programs from an inability to properly calibrate these systems, the RML has developed two alternative calibration techniques: 1) development and implementation of certified 32P sources for activity calibrations and subsequent calculation of neutron fluence, and 2) direct counting of non-certified reactor-irradiated sulfur pellets by liquid scintillation counting to determine 32P activity for the subsequent calibration of gas-flow proportional counters. Preliminary comparisons show that the several calibration methods are capable of overall uncertainties within about 5 percent.

The characterization of the neutron, prompt gamma-ray, and delayed gamma-ray radiation fields in the University of Texas at Austin Nuclear Engineering Teaching Laboratory (NETL) TRIGA reactor for the beam port (BP) 1/5 free-field environment at the 128-inch location adjacent to the core centerline has been accomplished. NETL is being explored as an auxiliary neutron test facility for the Sandia National Laboratories radiation effects sciences research and development campaigns. The NETL reactor is a TRIGA Mark-II pulse and steady-state, above-ground pool-type reactor. NETL is intended as a university research reactor typically used to perform irradiation experiments for students and customers, radioisotope production, as well as a training reactor. Initial criticality of the NETL TRIGA reactor was achieved on March 12, 1992, making it one of the newest test reactor facilities in the US. The neutron energy spectra, uncertainties, and covariance matrices are presented as well as a neutron fluence map of the experiment area of the cavity. For an unmoderated condition, the neutron fluence at the center of BP 1/5, at the adjacent core axial centerline, is about 8.2×1012 n/cm2 per MJ of reactor energy. About 67% of the neutron fluence is below 1 keV and 22% above 100 keV. The 1-MeV Damage-Equivalent Silicon (DES) fluence is roughly 1.6×1012 n/cm2 per MJ of reactor energy.

I. INTRODUCTION "The economic outlook Alaska faces today is dire." (1) This difficult situation may persist for some years. In 2014, the price of oil declined from $110 per barrel [...], The Alaska State budget has decreased in recent years, and because of the lower price of oil, it is not expected to recover in the near term. This smaller budgetary pie may intensify the impulse to protect the funding of individual projects. However, the Alaska Constitution forbids the dedication of taxes for specific purposes. This Essay proposes a state constitutional amendment that would allow such dedications, subject to limits designed to avoid potential problems. The Essay describes the effect the proposal would have had on past decisions of the Alaska Supreme Court and compares the dedication of tax revenue to the "New Property" identified by Charles Reich.

This study examined applications of polarized evanescent guided wave surface-enhanced Raman spectroscopy to determine the binding and orientation of small molecules and ligand-modified nanoparticles, and the relevance of this technique to lab-on-a-chip, surface plasmon polariton and other types of field enhancement techniques relevant to Raman biosensing. A simplified tutorial on guided-wave Raman spectroscopy is provided that introduces the notion of plasmonic nanoparticle field enhancements to magnify the otherwise weak TE- and TM-polarized evanescent fields for Raman scattering on a simple plasmonic nanoparticle slab waveguide substrate. The waveguide construct is called an optical chemical bench (OCB) to emphasize its adaptability to different kinds of surface chemistries that can be envisaged to prepare optical biosensors. The OCB forms a complete spectroscopy platform when integrated into a custom-built Raman spectrograph. Plasmonic enhancement of the evanescent field is achieved by attaching porous carpets of Au@Ag core shell nanoparticles to the surface of a multi-mode glass waveguide substrate. We calibrated the OCB by establishing the dependence of SER spectra of adsorbed 4-mercaptopyridine and 4-aminobenzoic acid on the TE/TM polarization state of the evanescent field. We contrasted the OCB construct with more elaborate photonic chip devices that also benefit from enhanced evanescent fields, but without the use of plasmonics. We assemble hierarchies of matter to show that the OCB can resolve the binding of Fe2+ ions from water at the nanoscale interface of the OCB by following the changes in the SER spectra of 4MPy as it coordinates the cation. A brief introduction to magnetoplasmonics sets the stage for a study that resolves the 4ABA ligand interface between guest magnetite nanoparticles adsorbed onto host plasmonic Au@Ag nanoparticles bound to the OCB. In some cases, the evanescent wave TM polarization was strongly attenuated, most likely due to damping by inertial charge carriers that favor optical loss for this polarization state in the presence of dense assemblies of plasmonic nanoparticles. The OCB offers an approach that provides vibrational and orientational information for (bio)sensing at interfaces that may supplement the information content of evanescent wave methods that rely on perturbations in the refractive index in the region of the evanescent wave. [ABSTRACT FROM AUTHOR]

The study of memory for texts has had an long tradition of re-search in psychology. According to most general accounts oftext memory, the recognition or recall of items in a text is basedon querying a memory representation that is built up on the ba-sis of background knowledge. The objective of this paper is todescribe and thoroughly test a Bayesian model of this generalaccount. In particular, we develop a model that describes howwe use our background knowledge to form memories as a pro-cess of Bayesian inference of the statistical patterns that areinherent in a text, followed by posterior predictive inference ofthe words that are typical of those inferred patterns. This pro-vides us with precise predictions about what words will be re-membered, whether veridically or erroneously, from any giventext. We then test these predictions using data from a memoryexperiment using a relatively large sample of randomly chosentexts from a representative corpus of British English.

Statistical learning paradigms traditionally use transitionalprobabilities as a measure of statistical distribution within alanguage. The current study suggests that alternative metricsmay exist that can account for differences in languageprocessing ability. Two primed lexical decision tasks are usedto examine the effects of bigram frequency and diversity onspeed and accuracy of word recognition. It is demonstratedthat both frequency and diversity contribute to wordrecognition performance; findings and theoreticalimplications are discussed.