Quantum Solitons Lead to Yukawa Coupling

Recently, it was shown that zero modes in semiclassical soliton models do not lead to Yukawa couplings. We show that taking into account the contributions of the quantum soliton into the renormalization scheme, which cannot be done in semiclassical treatments, leads to a Yukawa coupling. A similar analysis should be possible for the Skyrmion, renewing the hope, that this model will lead to a correct description of hadron physics.Comment: LATEX, Submitted to Phys. Lett.

Pre-implantation maternal uterine effects on embryo growth and development : an investigation using models of maternal constraint in sheep : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science, Massey University, Turitea, Palmerston North, New Zealand

Listed in 2017 Dean's List of Exceptional ThesesPrenatal development and growth are critical to survival of the fetus and neonate. Recent evidence suggests that a critical period for determining growth is the pre-implantation period of pregnancy during which differentiation, organogenesis and development of the embryo occur and the embryo is considerably vulnerable to uterine environmental factors. The objectives of the present study were to examine the effects of restrictive uterine environments on embryo development using two sheep models of maternal constraint: litter size and dam size, and to identify embryonic and maternally-driven mechanisms that regulate development of the peri-implantation sheep embryo. Morphometric analysis (embryo length, width and heart bulge width) of the embryos in peri-implantation single and twin embryos was inconclusive; as was the transcriptomics analysis of whole embryos using RNA-seq to examine differential gene expression that may be responsible for differential regulation of growth. In a dam size model, large-breed Suffolk embryos gestated in small-breed Cheviot ewes (constrained environment) were smaller than Suffolk embryos gestated in Suffolk ewes (control) at day 19 of pregnancy, confirming previous findings that maternal constraint is evident in early pregnancy when limitations of space are not of consequence. Progesterone administered in the post-ovulatory period, day 0 to 6, alleviates this apparent constraint such that Suffolk embryos gestated in Cheviot ewes that received progesterone are larger than those gestated in Cheviot ewes that did not. Further, differential gene expression analysis of maternal uterine tissues showed that at day 6 and day 19 endometrial genes that encode for histotroph secretion and uterine receptivity are altered by post-ovulatory progesterone administration. Timing of administration of progesterone is critical not only to embryo growth but also to embryo survival. There were lower pregnancy rates in the ewes that received progesterone from day 0 than those that received progesterone from day 2. The results of this thesis indicate that progesterone exerts its effects by regulation of genes that encode for uterine structural and secretory activity to advance the uterus. This likely forces the asynchronous embryo to accelerate its growth in order to adapt to its environment. These findings contribute to the knowledge of the regulatory mechanisms controlling early embryo growth and present a platform within the livestock industry and human reproductive technology practice to manipulate embryo growth to improve survival of offspring

The thermodynamics of human reaction times

I present a new approach for the interpretation of reaction time (RT) data from behavioral experiments. From a physical perspective, the entropy of the RT distribution provides a model-free estimate of the amount of processing performed by the cognitive system. In this way, the focus is shifted from the conventional interpretation of individual RTs being either long or short, into their distribution being\ud more or less complex in terms of entropy. The new approach enables the estimation of the cognitive processing load without reference to the informational content of the stimuli themselves, thus providing a more appropriate estimate of the cognitive impact of dierent sources of information that are carried by experimental stimuli or tasks. The paper introduces the formulation of the theory, followed by an empirical validation using a database of human RTs in lexical tasks (visual lexical decision and word\ud naming). The results show that this new interpretation of RTs is more powerful than the traditional one. The method provides theoretical estimates of the processing loads elicited by individual stimuli. These loads sharply distinguish the responses from different tasks. In addition, it provides upper-bound estimates for the speed at which the system processes information. Finally, I argue that the theoretical proposal, and the associated empirical evidence, provide strong arguments for an adaptive system that systematically adjusts its operational processing speed to the particular demands of each stimulus. This\ud finding is in contradiction with Hick's law, which posits a relatively constant processing speed within an experimental context

Stability of real parametric polynomial discrete dynamical systems

We extend and improve the existing characterization of the dynamics of general quadratic real polynomial maps with coefficients that depend on a single parameter $\lambda$, and generalize this characterization to cubic real polynomial maps, in a consistent theory that is further generalized to real $m$-th degree real polynomial maps. In essence, we give conditions for the stability of the fixed points of any real polynomial map with real fixed points. In order to do this, we have introduced the concept of Canonical Polynomial Maps which are topologically conjugate to any polynomial map of the same degree with real fixed points. The stability of the fixed points of canonical polynomial maps has been found to depend solely on a special function termed Product Position Function for a given fixed point. The values of this product position determine the stability of the fixed point in question, when it bifurcates, and even when chaos arises, as it passes through what we have termed stability bands. The exact boundary values of these stability bands are yet to be calculated for regions of type greater than one for polynomials of degree higher than three.Comment: 23 pages, 4 figures, now published in Discrete Dynamics in Nature and Societ

SUPPLY RESPONSE AND IMPACT OF GOVERNMENT-SUPPORTED CROPS ON THE TEXAS VEGETABLE INDUSTRY

Supply functions, elasticity estimates, and nonjointness test results consistently indicated that few commodities compete economically in the production of six major Texas vegetables (cabbage, cantaloupes, carrots, onions, potatoes, and watermelons). Significant bias effects caused by government-supported commodities, fixed inputs, and technological change were observed and measured. Nonnested test results for the hypothesis of sequential decision making by vegetable producers were inconclusive, but they gave greater likelihood support to sequential than to contemporaneous decision making.Demand and Price Analysis,