Rapid Dissolution for Destructive Assay of Nuclear Melt Glass

This study evaluates four methods for dissolving complex glassy debris resulting from nuclear detonations. The samples of interest simulate the glassy debris generated from a nuclear detonation’s fireball coming in contact with solid masses. Each method attempts to achieve dissolution through different approaches involving either acid digestion, alkaline digestion, or molten salt fusion. Two of the four methods were modified to retain all elements of the debris or surrogate debris. This retention is critical to the proportional relationships used in identifying fuel types and designs of nuclear weapons. Analysis is conducted with an inductively coupled time of flight mass spectrometer (ICP-TOF-MS) to provide exact elemental composition and yield for each dissolution method. The samples analyzed were trinitite (trin), surrogate trinitite formulation (STF), urban surrogate melt glass (NYC), and MAPEP MaS 32 (MAPEP). All samples have well known elemental compositions except for trinitite, however there are published compositional norms that are predicted for the trinitite. The four methods used were a Lithium Fusion (Larivière Method), a Sodium Hydroxide Fusion (Maxwell Method), an Acidic Digestion (Eppich Method), and a Modified Rapid Acidic Digestion (Auxier Method). Outcomes for the Lithium and the Maxwell Method failed to produce meaningful results due to the mass difference in fusion material compared to the isotopes of interest in the sample material mass. At the maximum concentration limit of 25-35 parts per thousand the mass spectrometer could not meaningfully detect the barium or uranium in any of the samples. The acidic digestion, and the Auxier Method both showed success with detecting appropriate levels of uranium, barium, and other lighter elements. The Auxier Method shows the best results when compared to ideal 100% yield from each sample. For Auxier’s Method, uranium averages a yield of 5%±.02% of ideal. This is 614% above the acidic digestion and over 1200% above the other methods. For barium, the Auxier Method averages a yield of 9% of ideal. This is 595% above the acidic digestion and 4300% above the other methods. The Auxier Method demonstrates repeatability across three runs of each sample and sample independence as percent yields were similar across sample types

Elements of the B Cell Signalosome Are Differentially Affected by Mercury Intoxication

It has been suggested that environmental exposures to mercury contribute to autoimmune disease. Disruption of BCR signaling is associated with failure of central tolerance and autoimmunity, and we have previously shown that low levels of Hg2+ interfere with BCR signaling. In this report we have employed multiparametric phosphoflow cytometry, as well as a novel generalization of the Overton algorithm from one- to two-dimensional unimodal distributions to simultaneously monitor the effect of low level Hg2+ intoxication on activation of ERK and several upstream elements of the BCR signaling pathway in WEHI-231 B cells. We have found that, after exposure to low levels of Hg2+, only about a third of the cells are sensitive to the metal. For those cells which are sensitive, we confirm our earlier work that activation of ERK is attenuated but now report that Hg2+ has little upstream effect on the Btk tyrosine kinase. On the other hand, we find that signaling upstream through the Syk tyrosine kinase is actually augmented, as is upstream activation of the B cell signalosome scaffolding protein BLNK

Master Equation Analysis of Thermochemical Nonequilibrium of Nitrogen

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97092/1/AIAA2012-3305.pd

Constraining Intermediate-Mass Black Holes in Globular Clusters

Decades after the first predictions of intermediate-mass black holes (IMBHs) in globular clusters (GCs) there is still no unambiguous observational evidence for their existence. The most promising signatures for IMBHs are found in the cores of GCs, where the evidence now comes from the stellar velocity distribution, the surface density profile, and, for very deep observations, the mass-segregation profile near the cluster center. However, interpretation of the data, and, in particular, constraints on central IMBH masses, require the use of detailed cluster dynamical models. Here we present results from Monte Carlo cluster simulations of GCs that harbor IMBHs. As an example of application, we compare velocity dispersion, surface brightness and mass-segregation profiles with observations of the GC M10, and constrain the mass of a possible central IMBH in this cluster. We find that, although M10 does not seem to possess a cuspy surface density profile, the presence of an IMBH with a mass up to 0.75% of the total cluster mass, corresponding to about 600 Msun, cannot be excluded. This is also in agreement with the surface brightness profile, although we find it to be less constraining, as it is dominated by the light of giants, causing it to fluctuate significantly. We also find that the mass-segregation profile cannot be used to discriminate between models with and without IMBH. The reason is that M10 is not yet dynamically evolved enough for the quenching of mass segregation to take effect. Finally, detecting a velocity dispersion cusp in clusters with central densities as low as in M10 is extremely challenging, and has to rely on only 20-40 bright stars. It is only when stars with masses down to 0.3 Msun are included that the velocity cusp is sampled close enough to the IMBH for a significant increase above the core velocity dispersion to become detectable.Comment: 30 pages, 8 figures, submitted to Ap

Airway expression of Transient Receptor Potential (TRP) Vanniloid-1 and Ankyrin-1 channels is not increased in patients with Idiopathic Pulmonary Fibrosis

Dry cough is a common symptom described in patients with Idiopathic Pulmonary Fibrosis (IPF) and impairs quality of life. The exact mechanisms causing cough in IPF remain unclear, however evidence suggests altered cough neurophysiology and sensitisation plays a role; IPF patients have an enhanced cough reflex sensitivity to inhaled capsaicin. The Transient Receptor Potential Vanniloid-1 channel (TRPV-1) has a role in the cough reflex and airway expression is increased in patients with chronic cough. The Ankyrin-1 receptor (TRPA-1) is often coexpressed. It was hypothesised that, like chronic cough patients, IPF patients have increased airway TRP receptor expression. Bronchial biopsies were obtained from 16 patients with IPF, 11 patients with idiopathic chronic cough and 8 controls without cough. All other causes of cough were rigorously excluded. Real-time quantitative Polymerase Chain Reaction was used to detect TRPV-1 and TRPA-1 mRNA expression with Immunohistochemistry demonstrating protein expression. Mean TRPV-1 and TRPA-1 gene expression was higher in IPF patients compared with controls, but the difference did not reach statistical significance. Immunostaining supported these findings. This study suggests that structural up-regulation of central airway TRP receptors is not the key mechanism for cough in IPF patients. It is probable that IPF cough results from altered neuronal sensitivity at multiple levels of the cough pathway

“Catch 22”: biosecurity awareness, interpretation and practice amongst poultry catchers

Campylobacter contamination of chicken on sale in the UK remains at high levels and has a substantial public health impact. This has prompted the application of many interventions in the supply chain, including enhanced biosecurity measures on-farm. Catching and thinning are acknowledged as threats to the maintenance of good biosecurity, yet the people employed to undertake this critical work (i.e. ‘catchers’) are a rarely studied group. This study uses a mixed methods approach to investigate catchers’ (n = 53) understanding of the biosecurity threats posed by the catching and thinning, and the barriers to good biosecurity practice. It interrogated the role of training in both the awareness and practice of good biosecurity. Awareness of lapses in biosecurity was assessed using a Watch-&-Click hazard awareness survey (n = 53). Qualitative interviews (n = 49 catchers, 5 farm managers) explored the understanding, experience and practice of catching and biosecurity. All of the catchers who took part in the Watch-&-Click study identified at least one of the biosecurity threats with 40% detecting all of the hazards. Those who had undergone training were significantly more likely to identify specific biosecurity threats and have a higher awareness score overall (48% compared to 9%, p = 0.03). Crucially, the individual and group interviews revealed the tensions between the high levels of biosecurity awareness evident from the survey and the reality of the routine practice of catching and thinning. Time pressures and a lack of equipment rather than a lack of knowledge appear a more fundamental cause of catcher-related biosecurity lapses. Our results reveal that catchers find themselves in a ‘catch-22′ situation in which mutually conflicting circumstances prevent simultaneous completion of their job and compliance with biosecurity standards