Reliable and robust molecular sexing of the hen harrier (Circus cyaneus) using PCR-RFLP of the CHD1 gene

The hen harrier (Circus cyaneus) is a bird of prey that is persecuted in the United Kingdom, and there is a need for a DNA-based individual identification and sexing system for the use in forensic investigations. This study reports a new set of PCR primers for the chromo-helicase-DNA-binding protein 1 gene, which allows sexing using PCR-RFLP. Instead of exonic primers that amplify across a large intron, this set consists of a primer within the intron, enabling reduction in amplicon sizes from 356 to 212 bp and 565 to 219 bp in W and Z chromosomes. DNA degradation and dilution experiments demonstrate that this set is significantly more robust than one that amplifies across the intron, and sequencing of the intronic primer-binding region across several individuals shows that it is highly conserved. While our objective is to incorporate this primer set into an STR-based individualization kit, it may in the meantime prove useful in forensic or conservation studies

Initial Results of a Silicon Sensor Irradiation Study for ILC Extreme Forward Calorimetry

Detectors proposed for the International Linear Collider (ILC) incorporate a tungsten sampling calorimeter (`BeamCal') intended to reconstruct showers of electrons, positrons and photons that emerge from the interaction point of the collider with angles between 5 and 50 milliradians. For the innermost radius of this calorimeter, radiation doses at shower-max are expected to reach 100 MRad per year, primarily due to minimum-ionizing electrons and positrons that arise in the induced electromagnetic showers of e+e- `beamstrahlung' pairs produced in the ILC beam-beam interaction. However, radiation damage to calorimeter sensors may be dominated by hadrons induced by nuclear interactions of shower photons, which are much more likely to contribute to the non-ionizing energy loss that has been observed to damage sensors exposed to hadronic radiation. We report here on the results of SLAC Experiment T-506, for which several different types of silicon diode sensors were exposed to doses of radiation induced by showering electrons of energy 3.5-10.6 GeV. By embedding the sensor under irradiation within a tungsten radiator, the exposure incorporated hadronic species that would potentially contribute to the degradation of a sensor mounted in a precision sampling calorimeter. Depending on sensor technology, efficient charge collection was observed for doses as large as 220 MRad.Comment: Talk presented at the International Workshop on Future Linear Colliders (LCWS13), Tokyo, Japan, 11-15 November 201

Recent Observations of Betelgeuse and New Instrumentation at the ISI

The Infrared Spatial Interferometer (ISI) has been conducting mid-infrared observations of late-type stars for about 18 years. A long-term set of diameter measurements of Betelgeuse at 11.15 μm shows pronounced changes in the stellar size over time. These changes may arise from variations in the opacity of the environment immediately surrounding the star. New instrumentation is being developed to identify the composition and kinematics of the circumstellar environment of Betelgeuse, and of other late-type stars. A digital spectrometer-correlator is being built and tested that will enable visibility measurements on and off individual molecular spectral lines. Results from testing the spectrometer system are presented

Raman and nuclear magnetic resonance investigation of alkali metal vapor interaction with alkene-based anti-relaxation coating

The use of anti-relaxation coatings in alkali vapor cells yields substantial performance improvements by reducing the probability of spin relaxation in wall collisions by several orders of magnitude. Some of the most effective anti-relaxation coating materials are alpha-olefins, which (as in the case of more traditional paraffin coatings) must undergo a curing period after cell manufacturing in order to achieve the desired behavior. Until now, however, it has been unclear what physicochemical processes occur during cell curing, and how they may affect relevant cell properties. We present the results of nondestructive Raman-spectroscopy and magnetic-resonance investigations of the influence of alkali metal vapor (Cs or K) on an alpha-olefin, 1-nonadecene coating the inner surface of a glass cell. It was found that during the curing process, the alkali metal catalyzes migration of the carbon-carbon double bond, yielding a mixture of cis- and trans-2-nonadecene.Comment: 5 pages, 6 figure

Terahertz plasmons in coupled two-dimensional semiconductor resonators

Advances in theory are needed to match recent progress in measurements of coupled semiconductor resonators supporting terahertz plasmons. Here, we present a field-based model of plasmonic resonators that comprise gated and ungated two-dimensional electron systems. The model is compared to experimental measurements of a representative system, in which the interaction between the gated and ungated modes leads to a rich spectrum of hybridized resonances. A theoretical framework is thus established for the analysis and design of gated low-dimensional systems used as plasmonic resonators, underlining their potential application in the manipulation of terahertz frequency range signals

The non-uniform, dynamic atmosphere of Betelgeuse observed at mid-infrared wavelengths

We present an interferometric study of the continuum surface of the red supergiant star Betelgeuse at 11.15 microns wavelength, using data obtained with the Berkeley Infrared Spatial Interferometer each year between 2006 and 2010. These data allow an investigation of an optically thick layer within 1.4 stellar radii of the photosphere. The layer has an optical depth of ~1 at 11.15 microns, and varies in temperature between 1900 K and 2800 K and in outer radius between 1.16 and 1.36 stellar radii. Electron-hydrogen atom collisions contribute significantly to the opacity of the layer. The layer has a non-uniform intensity distribution that changes between observing epochs. These results indicate that large-scale surface convective activity strongly influences the dynamics of the inner atmosphere of Betelgeuse, and mass-loss processes.Comment: 13 pages, 5 figures, in press (ApJ

Jackrabbit Dairy and Food Review

This is the Winter 2017- 2018 Jackrabbit Dairy and Food Review. It contains the following articles and information: Message from the Department Head, 2017 Graduates, David A. Thompson Endowment, New Faculty and Visitors, information on the Dairy Club and Food Science Club, Judging Activities, Student Accomplishments, Professional Activities of Faculty and Staff, Distinguished Alumni, Dairy Facilities, a list of Scholarships and Dairy and Food Science Students, information on Departmental Outreach and Research Highlights

Jackrabbit Dairy and Food Review

This is the Winter 2017- 2018 Jackrabbit Dairy and Food Review. It contains the following articles and information: Message from the Department Head, 2017 Graduates, New Faculty and Visitors, information on the Dairy Club and Food Science Club, Judging Activities, Student Accomplishments, Professional Activities of Faculty and Staff, Distinguished Alumni, Dairy Facilities, a list of Scholarships and Dairy and Food Science Students, information on Departmental Outreach and Research Highlights

Modelling the mechanisms of nitridation of SiC based devices during anneals in NH3 and NO gases

The work presented in this thesis is focused on the mechanisms of processes thatoccur during the NO and NH3anneals of 4H-SiC/a-SiO2devices, specifically on thenitridation of performance limiting defects in a-SiO2. All results are found usingdensity functional theory (DFT) and classical molecular dynamics.The first two results chapters of this thesis investigate the interactions of nitricoxide (NO) and ammonia (NH3) with a pristine a-SiO2network. This investigationis important on two fronts, the first is that the oxide used in these devices is of highquality (CVD oxide), and the second is that these molecules have been shown to in-corporate into the oxide and, in some cases, chemically interact with it. Hence onemust understand the interactions of these molecules with the pristine a-SiO2. My re-sults demonstrate that neutral NO molecules only have steric repulsive interactionswith the pristine network and negative NO molecule interacts with the network Siatoms electrostatically. These interactions manifest as higher NO migration barri-ers in the negative charge state compared to the neutral charge state. Ammonia isshown to form similar interstitials but also react with the surface silanol groups toform smaller ammonia fragments, like NH2and NH, which then lead to nitridationseen in elemental studies of such devices.In the next chapter I examine the interaction of NO and NH3fragments withcommon defects in the a-SiO2network. The results in this chapter show how thecharge transition levels (CTLs) of known oxide defects move deeper into the SiC/a-SiO2band gap, on nitridation, leading to the conclusion that the tunnelling proba-bility to these defects decreases due to the large difference in energy between theSiC CBM and the nitridated defect levels. In the final chapter I present the results of simulations of the structure and properties of a SiC/a-SiO2interface as well asthe effects of proximity of the interface for defect properties. Finally, I discuss thecharacter of surface relaxation of the a-face of 4H-SiC