Dry-Milling and Fractionation of Transgenic Maize Seed Tissues with Green Fluorescent Protein as a Tissue Marker

The efficiency of fractionating cereal grains (e.g., dry corn milling) can be evaluated and monitored by quantifying the proportions of seed tissues in each of the recovered fractions. The quantities of individual tissues are typically estimated using indirect methods such as quantifying fiber or ash to indicate pericarp and tip cap contents, and oil to indicate germ content. More direct and reliable methods are possible with tissue-specific markers. We used two transgenic maize lines, one containing the fluorescent protein green fluorescent protein (GFP) variant S65T expressed in endosperm, and the other containing GFP expressed in germ to determine the fate of each tissue in the dry-milling fractionation process. The two lines were dry-milled to produce three fractions (bran-, endosperm-, and germ-rich fractions) and GFP fluorescence was quantified in each fraction to estimate the tissue composition. Using a simplified laboratory dry-milling procedure and our GFP-containing grain, we determined that the endosperm-rich fraction contained 4% germ tissue, the germ-rich fraction contained 28% germ, 20% endosperm, and 52% nonendosperm and nonembryo tissues, and the bran-rich fraction contained 44% endosperm, 13% germ, and 43% nonendosperm and nonembryo tissues. GFP-containing grain can be used to optimize existing fractionation methods and to develop improved processing strategies

Green Fluorescent Protein as a Tissue Marker in Transgenic Maize Seed

Seed tissues (endosperm, embryo, and pericarp) are often separated into tissue-enriched fractions by wet- or dry-milling methods for use in food, feed, and industrial products. Seed tissue markers that are sensitive and readily quantifiable would be useful to optimize fractionation processes. To meet this need for tissue markers, we set out to produce and characterize different transgenic maize lines, each containing green fluorescent protein (GFP) in either endosperm or embryo. We examined mRNA transcripts using expressed sequence tag (EST) profiles of several major seed proteins and selected several with strong seed tissue preferences. Stably transformed maize lines were produced, and visual observation of fluorescence confirmed the presence of GFP in the desired tissues. To establish the utility of this grain for evaluating the effectiveness or separation efficiencies of fractionation processes, transgenic kernels were hand-dissected into pericarp, endosperm, and embryo fractions and the GFP concentration in each fraction was determined. The GFP distribution between fractions of each transgenic event was calculated from GFP concentration and mass balance, which enabled the determination of GFP yield based on the hand-dissection fractionation data and the amount of tissue contamination in each fraction. Our transgenic lines exhibited strong tissue preference for either embryo or endosperm. These lines should be useful for assessing separation efficiencies in maize fractionation processes

No room at the top? The glass wall for professional services managers in pre-1992 English universities

Pre-1992 English universities are changing the way they appoint their deputy and pro-vice-chancellors (PVCs). Traditionally, PVC posts were filled by internal secondment from within the professoriate, but these days an increasing number are appointed by means of external open competition involving advertisement and/or executive search. So has this ‘opening up’ of PVC positions created new career progression opportunities for professional services managers? Findings from a census, online survey and interviews with a range of senior university managers suggest not. Despite the PVC role becoming more managerial, those getting the jobs remain overwhelmingly career academics. Professional services managers confront a glass wall, excluded from consideration by a non-negotiable requirement for academic credibility. Aware they have little chance of getting a PVC job, they are unlikely to apply. The continued monopolisation of PVC posts by academic managers represents a form of social closure that serves to maintain their elite status

A Study of the \eta \pi^{0} Spectrum and Search for a J^{PC} = 1^{-+} Exotic Meson

A partial wave analysis (PWA) of the of the $\eta \pi ^0$ system (where $\eta \to \gamma \gamma$) produced in the charge exchange reaction $\pi ^-p\to \eta \pi ^0n$ at an incident momentum of 18 GeV$/c$ is presented as a function of ${\eta \pi ^0}$ invariant mass, $m_{\eta\pi^0}$, and momentum transfer squared, $t_{\pi^{-}\to\eta\pi}$, from the incident $\pi^-$ to the outgoing ${\eta\pi ^0}$ system. $S$, $P$ and $D$ waves were included in the PWA. The $a_0(980)$ and $a_2(1320)$ states are clearly observed in the overall ${\eta\pi ^0}$ effective mass distribution as well as in the amplitudes associated with $S$ wave and $D$ waves respectively after partial wave decomposition. The observed distributions in moments (averages of spherical harmonics) were compared to the results from the PWA and the two are consistent. The distribution in $t_{\pi^{-}\to\eta\pi}$ for individual $D$ waves associated with natural and unnatural parity exchange in the $t$-channel are consistent with Regge phenomenology. Of particular interest in this study is the $P$ wave since this leads to an exotic $J^{PC}=1^{-+}$ for the $\eta \pi$ system. A $P$ wave is present in the data, however attempts to describe the mass dependence of the amplitude and phase motion with respect to the $D$ wave as a Breit-Wigner resonance are problematic. This has implications regarding the existence of a reported exotic $J^{PC} = 1^{-+}$ meson decaying into $\eta \pi^0$ with a mass near 1.4 GeV$/c^2$.Comment: 19 pages, 29 figures, to appear in Phys. Rev.

A 31 GHz Survey of Low-Frequency Selected Radio Sources

The 100-m Robert C. Byrd Green Bank Telescope (GBT) and the Owens Valley Radio Observatory (OVRO) 40-m radio telescope have been used to conduct a survey of 3165 known extragalactic radio sources over 143 square degrees of the sky. Target sources were selected from the NRAO VLA Sky Survey in fields observed by the Cosmic Background Imager (CBI); most are extragalactic active galactic nuclei (AGN) with 1.4 GHz flux densities of 3 to 10 mJy. The resulting 31 GHz catalogs are presented in full online. Using a Maximum-Likelihood analysis to obtain an unbiased estimate of the distribution of the 1.4 to 31 GHz spectral indices of these sources, we find a mean 31 to 1.4 GHz flux ratio of 0.110 +/- 0.003 corresponding to a spectral index of alpha=-0.71 +/- 0.01 (S ~ nu^alpha); 9.0 +/- 0.8 % of sources have alpha > -0.5 and 1.2 +/- 0.2 % have alpha > 0. By combining this spectral index distribution with 1.4 GHz source counts we predict 31 GHz source counts in the range 1 mJy < S_31 < 4 mJy, N(>S_31) = (16.7 +/- 1.7) deg^2 (S_31/1 mJy)^(-0.80 +/- 0.07). We also assess the contribution of mJy-level (S_1.4 < 3.4 mJy) radio sources to the 31 GHz CMB power spectrum, finding a mean power of ell (ell+1) C^src_ell/(2 pi) = 44 +/- 14 micro-Kelvin^2 and a 95% upper limit of 80 micro-Kelvin^2 at ell = 2500. Including an estimated contribution of 12 micro-Kelvin^2 from the population of sources responsible for the turn-up in counts below S_1.4 = 1 mJy this amounts to 21 +/- 7 % of what is needed to explain the CBI high-ell excess signal, 275 +/- 63 micro-Kelvin^2. These results are consistent with other measurements of the 31 GHz point source foreground.Comment: Replace with accepted version, incorporating referee comments. Significant revisions for clarity, added comparison to recent results. Quoted error bars on source counts are larger and the range of validity more limited; results on CBI excess unchange

Quasi-probability representations of quantum theory with applications to quantum information science

This article comprises a review of both the quasi-probability representations of infinite-dimensional quantum theory (including the Wigner function) and the more recently defined quasi-probability representations of finite-dimensional quantum theory. We focus on both the characteristics and applications of these representations with an emphasis toward quantum information theory. We discuss the recently proposed unification of the set of possible quasi-probability representations via frame theory and then discuss the practical relevance of negativity in such representations as a criteria for quantumness.Comment: v3: typos fixed, references adde

Les Houches 2011: Physics at TeV Colliders New Physics Working Group Report

We present the activities of the "New Physics" working group for the "Physics at TeV Colliders" workshop (Les Houches, France, 30 May-17 June, 2011). Our report includes new agreements on formats for interfaces between computational tools, new tool developments, important signatures for searches at the LHC, recommendations for presentation of LHC search results, as well as additional phenomenological studies.Comment: 243 pages, report of the Les Houches 2011 New Physics Group; fix three figure