More Cappell-Shaneson spheres are standard

Akbulut has recently shown that an infinite family of Cappell-Shaneson homotopy 4-spheres is diffeomorphic to the standard 4-sphere. In the present paper, a strictly larger family is shown to be standard by a simpler method. This new approach uses no Kirby calculus except through the relatively simple 1979 paper of Akbulut and Kirby showing that the simplest example with untwisted framing is standard. Instead, hidden symmetries of the original Cappell-Shaneson construction are exploited. In the course of the proof, we give an example showing that Gluck twists can sometimes be undone using symmetries of fishtail neighborhoods.Comment: 11 pages, 2 figures. This (v2) is essentially the published version, with minor mathematical improvements over v

Who Holds the Mirror? The Creation of an Ideal Vietnamese Woman, 1918-1934.

M.A. Thesis. University of Hawaiʻi at Mānoa 2018

Cereal straw and stubble for sheep feed

Many farmers in Western Australia run sheep in addition to their cropping programmes. The resulting cereal straws and stubbles are therefore important as sheep feed during summer and autumn. During this period the diet must provide sufficient energy to maintain liveweight, but additional energy and protein may be required for young stock and pregnant or lactating ewes, and to reduce problems from tender wool

Mammary Cell Cyclic AMP: Regulation of Breakdown and Influence on Protein Phosphorylation

This thesis addresses the question of whether certain control mechanisms responsible for metabolic regulation in mammalian tissues such as liver, adipose tissue and muscle, are also functional in mammary tissue. Cyclic AMP-dependent phosphorylation is considered ubiquitous in animal tissues and has been demonstrated to be capable of regulating numerous major metabolic pathways (see section 1.). In mammary tissue, cellular metabolism is dominated overwhelmingly by lactogenesis: the biosynthesis of lipid is a principal pathway in the collection of activities comprising this function. The cyclic AMP-dependent regulation of this and other metabolic pathways of particular relevance to mammary cell function is discussed at length in section 1., highlighting the apparent necessity for control mechanisms analogous to those found in other cell types. A review of these mechanisms demonstrates the potential importance of cyclic AMP as a regulator of mammary cell metabolism and raises many interesting questions. One of the most intriguing of these is whether or not mammary cell cyclic AMP levels are subject to the same regulatory influences as have been described for tissues such as liver and adipose tissue. An obvious extension of this is whether modulation of intracellular cyclic AMP levels provokes the same metabolic response, in mammary tissue, as has been observed in these other tissues. Both of these questions have been addressed and the results are presented here. The discovery that the activity of a high affinity form of cyclic AMP-phosphodiesterase found in adipose tissue and liver can be modulated by hormones such as insulin has stimulated a great deal of interest since it provides a possible mechanism for at least some of the metabolic effects of this hormone. Mammary tissue also contains "high affinity" cyclic AMP-phosphodiesterase and its regulatory properties, particularly with respect to insulin-sensitivity, have been investigated. The results show that rat mammary high affinity cyclic AMP phosphodiesterase activity is stimulated by treatment of isolated acinus preparations with insulin but that the effect cannot be reproduced in a broken-cell system. These results are discussed with reference to similar studies in other tissues. Although intracellular cyclic AMP concentrations can be raised many-fold by treatment of mammary cells with agents such as forskolin and B-adrenergic agonists (in the presence of a phosphodiesterase inhibitor), no discernable effect on the activity of key enzymes such as acetyl-CoA carboxylase (known to be phosphorylated and inactivated by cyclic AMP-dependent protein kinase) has been observed. Consequently, the existence, in mammary tissue, of a competent combination of cyclic AMP-dependent protein kinase and endogenous substrate has been investigated. Complementary to this, a preliminary survey of the existence in mammary tissue, of three other effector-dependent phosphorylation systems (governed by calcium/calmodulin-dependent protein kinase, protein kinase C and polyamine-dependent protein kinase) has been conducted. The major finding was that rat mammary tissue does indeed contain competent kinase/endogenous substrate combinations for at least two known effectors of metabolic regulation. One of these is Ca2+/calmodulin but of greater significance to the present study, the other is cyclic AMP, for which phosphorylation was shown to display a dose-dependent relationship (in the physiological range) with at least two endogenous substrates. The molecular weights of these and other endogenous substrates for effector-dependent phosphorylation in mammary tissue are compared with substrates for similar phosphorylations already identified (in the literature) in other tissues

The scientific heritage of Richard Henry Dalitz, FRS (1925-2006)

Professor Richard H. Dalitz passed away on January 13, 2006. He was almost 81 years old and his outstanding contributions are intimately connected to some of the major breakthroughs of the 20th century in particle and nuclear physics. These outstanding contributions go beyond the Dalitz Plot, Dalitz Pair and CDD poles that bear his name. He pioneered the theoretical study of strange baryon resonances, of baryon spectroscopy in the quark model, and of hypernuclei, to all of which he made lasting contributions. His formulation of the "$\theta-\tau$ puzzle" led to the discovery that parity is not a symmetry of the weak interactions. A brief scientific evaluation of Dalitz's major contributions to particle and nuclear physics is hereby presented, followed by the first comprehensive list of his scientific publications, as assembled from several sources. The list is divided into two categories: the first, main part comprises Dalitz's research papers and reviews, including topics in the history of particle physics, biographies and reminiscences; the second part lists book reviews, public lectures and obituaries authored by Dalitz, and books edited by him. This provides the first necessary step towards a more systematic research of the Dalitz heritage in modern physics. The present 2016 edition updates the original 2006 edition, published in Nucl. Phys. A 771 (2006) 2-7, doi:10.1016/j.nuclphysa.2006.03.007, and 8-25, doi:10.1016/j.nuclphysa.2006.03.008, by including for the first time a dozen or so of publications, found recently in a list submitted to the Royal Society by Dalitz in 2004, that escaped our attention in the original version.Comment: updates the original edition by including several publications, mostly in category III, that were unknown to us in 200

Understanding Heisenberg's 'Magical' Paper of July 1925: a New Look at the Calculational Details

In July 1925 Heisenberg published a paper [Z. Phys. 33, 879-893 (1925)] which ended the period of `the Old Quantum Theory' and ushered in the new era of Quantum Mechanics. This epoch-making paper is generally regarded as being difficult to follow, perhaps partly because Heisenberg provided few clues as to how he arrived at the results which he reported. Here we give details of calculations of the type which, we suggest, Heisenberg may have performed. We take as a specific example one of the anharmonic oscillator problems considered by Heisenberg, and use our reconstruction of his approach to solve it up to second order in perturbation theory. We emphasize that the results are precisely those obtained in standard quantum mechanics, and suggest that some discussion of the approach - based on the direct computation of transition amplitudes - could usefully be included in undergraduate courses in quantum mechanics.Comment: 24 pages, no figures, Latex, submitted to Am. J. Phy

Searching for Quantum Solitons in a 3+1 Dimensional Chiral Yukawa Model

We search for static solitons stabilized by heavy fermions in a 3+1 dimensional Yukawa model. We compute the renormalized energy functional, including the exact one-loop quantum corrections, and perform a variational search for configurations that minimize the energy for a fixed fermion number. We compute the quantum corrections using a phase shift parameterization, in which we renormalize by identifying orders of the Born series with corresponding Feynman diagrams. For higher-order terms in the Born series, we develop a simplified calculational method. When applicable, we use the derivative expansion to check our results. We observe marginally bound configurations at large Yukawa coupling, and discuss their interpretation as soliton solutions subject to general limitations of the model.Comment: 27 pp., 7 EPS files; email correspondence to [email protected]

The complex relation between production and scattering amplitudes

The unitarity relation, Im(A)=T* A, is derived for a three-body production amplitude, A, that consists of a complex linear combination of elements of the two-body scattering amplitude, T. We conclude that the unitarity relation does not impose a realness condition on the coefficients in the expansion of, A, in terms of, T.Comment: 4 pages plain LaTe